test/Tools/isac/Knowledge/rational.sml
changeset 60327 464109593df0
parent 60326 33e04eb1a2f0
child 60328 cc02d2cc2e24
     1.1 --- a/test/Tools/isac/Knowledge/rational.sml	Thu Jul 15 20:09:44 2021 +0200
     1.2 +++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.3 @@ -1,1919 +0,0 @@
     1.4 -(* Title: tests for rationals
     1.5 -   Author: Walther Neuper
     1.6 -   Use is subject to license terms.
     1.7 -*)
     1.8 -
     1.9 -"-----------------------------------------------------------------------------";
    1.10 -"-----------------------------------------------------------------------------";
    1.11 -"table of contents -----------------------------------------------------------";
    1.12 -"-----------------------------------------------------------------------------";
    1.13 -"-------- fun poly_of_term ---------------------------------------------------";
    1.14 -"-------- fun is_poly --------------------------------------------------------";
    1.15 -"-------- fun term_of_poly ---------------------------------------------------";
    1.16 -"-------- integration lev.1 fun factout_p_ -----------------------------------";
    1.17 -"-------- integration lev.1 fun cancel_p_ ------------------------------------";
    1.18 -"-------- integration lev.1 fun common_nominator_p_ --------------------------";
    1.19 -"-------- integration lev.1 fun add_fraction_p_ ------------------------------";
    1.20 -"Rfuns-------- and app_rev ...traced down from rewrite_set_ until prepats ---------";
    1.21 -"Rfuns-------- fun rewrite_set_ cancel_p downto fun gcd_poly ----------------------";
    1.22 -"-------- rls norm_Rational downto fun gcd_poly ------------------------------";
    1.23 -"Rfuns-------- rls norm_Rational downto fun add_fraction_p_ -----------------------";
    1.24 -"----------- rewrite_set_ Partial_Fractions norm_Rational --------------------------------------";
    1.25 -"----------- fun check_frac_sum with Free A and Const AA ---------------------------------------";
    1.26 -"----------- fun cancel_p with Const AA --------------------------------------------------------";
    1.27 -"-------- rewrite_set_ cancel_p from: Mathematik 1 Schalk Reniets Verlag -----";
    1.28 -"-------- rewrite_set_ add_fractions_p from: Mathematik 1 Schalk -------------";
    1.29 -"-------- integration lev.1 -- lev.5: cancel_p_ & add_fractions_p_ -----------";
    1.30 -"Rfuns-------- reverse rewrite ----------------------------------------------------";
    1.31 -"Rfuns-------- 'reverse-ruleset' cancel_p -----------------------------------------";
    1.32 -"-------- investigate rls norm_Rational --------------------------------------";
    1.33 -"-------- examples: rls norm_Rational ----------------------------------------";
    1.34 -"-------- rational numerals --------------------------------------------------";
    1.35 -"-------- examples cancellation from: Mathematik 1 Schalk --------------------";
    1.36 -"-------- examples common denominator from: Mathematik 1 Schalk --------------";
    1.37 -"-------- examples multiply and cancel from: Mathematik 1 Schalk -------------";
    1.38 -"-------- examples common denominator and multiplication from: Schalk --------";
    1.39 -"-------- examples double fractions from: Mathematik 1 Schalk ----------------";
    1.40 -"-------- me Schalk I No.186 -------------------------------------------------";
    1.41 -"-------- interSteps ..Simp_Rat_Double_No-1.xml ------------------------------";
    1.42 -"-------- interSteps ..Simp_Rat_Cancel_No-1.xml ------------------------------";
    1.43 -"-------- investigate rulesets for cancel_p ----------------------------------";
    1.44 -"-------- fun eval_get_denominator -------------------------------------------";
    1.45 -"-------- several errpats in complicated term --------------------------------";
    1.46 -"-------- WN1309xx non-terminating rls norm_Rational -------------------------";
    1.47 -"-----------------------------------------------------------------------------";
    1.48 -"-----------------------------------------------------------------------------";
    1.49 -
    1.50 -
    1.51 -"-------- fun poly_of_term ---------------------------------------------------";
    1.52 -"-------- fun poly_of_term ---------------------------------------------------";
    1.53 -"-------- fun poly_of_term ---------------------------------------------------";
    1.54 -val thy = @{theory Partial_Fractions};
    1.55 -val vs = TermC.vars_of (TermC.str2term "12 * x \<up> 3 * y \<up> 4 * z \<up> 6");
    1.56 -
    1.57 -val t = TermC.str2term "-3 + -2 * x ::real";
    1.58 -if poly_of_term vs t = SOME [(~3, [0, 0, 0]), (~2, [1, 0, 0])]
    1.59 -then () else error "poly_of_term uminus changed";
    1.60 -
    1.61 -if poly_of_term vs (TermC.str2term "12::real") = SOME [(12, [0, 0, 0])]
    1.62 -then () else error "poly_of_term 1 changed";
    1.63 -
    1.64 -if poly_of_term vs (TermC.str2term "x::real") = SOME [(1, [1, 0, 0])]
    1.65 -then () else error "poly_of_term 2 changed";
    1.66 -
    1.67 -if         poly_of_term vs (TermC.str2term "12 * x \<up> 3") = SOME [(12, [3, 0, 0])]
    1.68 -then () else error "poly_of_term 3 changed";
    1.69 -"~~~~~ fun poly_of_term , args:"; val (vs, t) =
    1.70 -  (vs, (TermC.str2term "12 * x \<up> 3"));
    1.71 -
    1.72 -           monom_of_term vs (1, replicate (length vs) 0) t;(*poly malformed 1 with x \<up> 3*)
    1.73 -"~~~~~ fun monom_of_term , args:"; val (vs, (c, es), (Const ("Groups.times_class.times", _) $ m1 $ m2)) =
    1.74 -  (vs, (1, replicate (length vs) 0), t);
    1.75 -    val (c', es') =
    1.76 -
    1.77 -           monom_of_term vs (c, es) m1;
    1.78 -"~~~~~ fun monom_of_term , args:"; val (vs, (c, es), (Const ("Transcendental.powr", _) $ (t as Free _) $ (Const ("Num.numeral_class.numeral", _) $ num)) ) =
    1.79 -  (vs, (c', es'), m2);
    1.80 -(*+*)c = 12;
    1.81 -(*+*)(num |> HOLogic.dest_numeral |> list_update es (find_index (curry op = t) vs)) = [3, 0, 0];
    1.82 -
    1.83 -if (c, num |> HOLogic.dest_numeral |> list_update es (find_index (curry op = t) vs)) = (12, [3, 0, 0])
    1.84 -then () else error "monom_of_term (powr): return value CHANGED";
    1.85 -
    1.86 -if poly_of_term vs (TermC.str2term "12 * x \<up> 3 * y \<up> 4 * z \<up> 6") = SOME [(12, [3, 4, 6])]
    1.87 -then () else error "poly_of_term 4 changed";
    1.88 -
    1.89 -if poly_of_term vs (TermC.str2term "1 + 2 * x \<up> 3 * y \<up> 4 * z \<up> 6 + y") =
    1.90 -  SOME [(1, [0, 0, 0]), (1, [0, 1, 0]), (2, [3, 4, 6])]
    1.91 -then () else error "poly_of_term 5 changed";
    1.92 -
    1.93 -(*poly_of_term is quite liberal:*)
    1.94 -(*the coefficient may be somewhere, the order of variables and the parentheses 
    1.95 -  within a monomial are arbitrary*)
    1.96 -if poly_of_term vs (TermC.str2term "y \<up> 4 * (x \<up> 3 * 12 * z \<up> 6)") = SOME [(12, [3, 4, 6])]
    1.97 -then () else error "poly_of_term 6 changed";
    1.98 -
    1.99 -(*there may even be more than 1 coefficient:*)
   1.100 -if poly_of_term vs (TermC.str2term "2 * y \<up> 4 * (x \<up> 3 * 6 * z \<up> 6)") = SOME [(12, [3, 4, 6])]
   1.101 -then () else error "poly_of_term 7 changed";
   1.102 -
   1.103 -(*the order and the parentheses within monomials are arbitrary:*)
   1.104 -if poly_of_term vs (TermC.str2term "2 * x \<up> 3 * y \<up> 4 * z \<up> 6 + (7 * y \<up> 8 + 1)")
   1.105 -  = SOME [(1, [0, 0, 0]), (7, [0, 8, 0]), (2, [3, 4, 6])]
   1.106 -then () else error "poly_of_term 8 changed";
   1.107 -
   1.108 -(*from --- rls norm_Rational downto fun gcd_poly ---*)
   1.109 -val t = TermC.str2term (*copy from above: "::real" is not required due to " \<up> "*)
   1.110 -  ("(-12 + 4 * y + 3 * x \<up> 2 + -1 * (x \<up> 2 * y)) /" ^
   1.111 -  "(-18 + -9 * x + 2 * y \<up> 2 + x * y \<up> 2)");
   1.112 -"~~~~~ fun cancel_p_, args:"; val (t) = (t);
   1.113 -val opt = check_fraction t;
   1.114 -val SOME (numerator, denominator) = opt;
   1.115 -(*+*)UnparseC.term numerator = "- 12 + 4 * y + 3 * x \<up> 2 + - 1 * (x \<up> 2 * y)"; (*isa -- isa2*);
   1.116 -(*+*)UnparseC.term denominator = "- 18 + - 9 * x + 2 * y \<up> 2 + x * y \<up> 2";     (*isa -- isa2*);
   1.117 -       val vs = TermC.vars_of t;
   1.118 -(*+*)UnparseC.terms vs = "[\"x\", \"y\"]";
   1.119 -       val baseT = type_of numerator
   1.120 -       val expT = HOLogic.realT;
   1.121 -val (SOME _, SOME _) = (poly_of_term vs numerator, poly_of_term vs denominator);  (*isa <> isa2*)
   1.122 -
   1.123 -"-------- fun is_poly --------------------------------------------------------";
   1.124 -"-------- fun is_poly --------------------------------------------------------";
   1.125 -"-------- fun is_poly --------------------------------------------------------";
   1.126 -if is_poly (TermC.str2term "2 * x \<up> 3 * y \<up> 4 * z \<up> 6 + 7 * y \<up> 8 + 1")
   1.127 -then () else error "is_poly 1 changed";
   1.128 -if not (is_poly (TermC.str2term "2 * (x \<up> 3 * y \<up> 4 * z \<up> 6 + 7) * y \<up> 8 + 1"))
   1.129 -then () else error "is_poly 2 changed";
   1.130 -
   1.131 -"-------- fun term_of_poly ---------------------------------------------------";
   1.132 -"-------- fun term_of_poly ---------------------------------------------------";
   1.133 -"-------- fun term_of_poly ---------------------------------------------------";
   1.134 -val expT = HOLogic.realT
   1.135 -val Free (_, baseT) = (hd o vars o TermC.str2term) "12 * x \<up> 3 * y \<up> 4 * z \<up> 6";
   1.136 -val p = [(1, [0, 0, 0]), (7, [0, 8, 0]), (2, [3, 4, 5])]
   1.137 -val vs = TermC.vars_of (the (parseNEW ctxt "12 * x \<up> 3 * y \<up> 4 * z \<up> 6"))
   1.138 -(*precondition for [(c, es),...]: legth es = length vs*)
   1.139 -;
   1.140 -if UnparseC.term (term_of_poly baseT expT vs p) = "1 + 7 * y \<up> 8 + 2 * x \<up> 3 * y \<up> 4 * z \<up> 5"
   1.141 -then () else error "term_of_poly 1 changed";
   1.142 -
   1.143 -"-------- integration lev.1 fun factout_p_ -----------------------------------";
   1.144 -"-------- integration lev.1 fun factout_p_ -----------------------------------";
   1.145 -"-------- integration lev.1 fun factout_p_ -----------------------------------";
   1.146 -val t = TermC.str2term "(x \<up> 2 + -1*y \<up> 2) / (x \<up> 2 + -1*x*y)"
   1.147 -val SOME (t', asm) = factout_p_ thy t;
   1.148 -if UnparseC.term t' = "(x + y) * (x + - 1 * y) / (x * (x + - 1 * y))"
   1.149 -then () else error ("factout_p_ term 1 changed: " ^ UnparseC.term t')
   1.150 -;
   1.151 -if UnparseC.terms asm = "[\"x \<noteq> 0\", \"x + - 1 * y \<noteq> 0\"]"
   1.152 -then () else error "factout_p_ asm 1 changed"
   1.153 -;
   1.154 -val t = TermC.str2term "nothing + to_cancel ::real";
   1.155 -if NONE = factout_p_ thy t then () else error "factout_p_ doesn't report non-applicable";
   1.156 -;
   1.157 -val t = TermC.str2term "((3 * x \<up> 2 + 6 *x + 3) / (2*x + 2))";
   1.158 -val SOME (t', asm) = factout_p_ thy t;
   1.159 -if UnparseC.term t' = "(3 + 3 * x) * (1 + x) / (2 * (1 + x))" andalso 
   1.160 -  UnparseC.terms asm = "[\"1 + x \<noteq> 0\"]"
   1.161 -then () else error "factout_p_ 1 changed";
   1.162 -
   1.163 -"-------- integration lev.1 fun cancel_p_ ------------------------------------";
   1.164 -"-------- integration lev.1 fun cancel_p_ ------------------------------------";
   1.165 -"-------- integration lev.1 fun cancel_p_ ------------------------------------";
   1.166 -val t = TermC.str2term "(x \<up> 2 + -1*y \<up> 2) / (x \<up> 2 + -1*x*y)"
   1.167 -val SOME (t', asm) = cancel_p_ thy t;
   1.168 -if (UnparseC.term t', UnparseC.terms asm) = ("(x + y) / x", "[\"x \<noteq> 0\"]")
   1.169 -then () else error ("cancel_p_ (t', asm) 1 changed: " ^ UnparseC.term t')
   1.170 -;
   1.171 -val t = TermC.str2term "nothing + to_cancel ::real";
   1.172 -if NONE = cancel_p_ thy t then () else error "cancel_p_ doesn't report non-applicable";
   1.173 -;
   1.174 -val t = TermC.str2term "((3 * x \<up> 2 + 6 *x + 3) / (2*x + 2))";
   1.175 -val SOME (t', asm) = cancel_p_ thy t;
   1.176 -if UnparseC.term t' = "(3 + 3 * x) / 2" andalso UnparseC.terms asm = "[]"
   1.177 -then () else error "cancel_p_ 1 changed";
   1.178 -
   1.179 -"-------- integration lev.1 fun common_nominator_p_ --------------------------";
   1.180 -"-------- integration lev.1 fun common_nominator_p_ --------------------------";
   1.181 -"-------- integration lev.1 fun common_nominator_p_ --------------------------";
   1.182 -val t = TermC.str2term ("y / (a*x + b*x + c*x) " ^
   1.183 -              (* n1    d1                   *)
   1.184 -                "+ a / (x*y)");
   1.185 -              (* n2    d2                   *)
   1.186 -val SOME (t', asm) = common_nominator_p_ thy t;
   1.187 -if UnparseC.term t' =
   1.188 -      ("y * y / (x * ((a + b + c) * y)) " ^
   1.189 -  (*  n1  *d2'/ (c'* ( d1'        *d2')) *)
   1.190 -     "+ a * (a + b + c) / (x * ((a + b + c) * y))")
   1.191 -   (*  n2 * d1'         / (c'* ( d1'        *d2')) *)
   1.192 -then () else error "common_nominator_p_ term 1 changed";
   1.193 -if UnparseC.terms asm = "[\"a + b + c \<noteq> 0\", \"y \<noteq> 0\", \"x \<noteq> 0\"]"
   1.194 -then () else error "common_nominator_p_ asm 1 changed"
   1.195 -
   1.196 -"-------- example in mail Nipkow";
   1.197 -val t = TermC.str2term "x/(x \<up> 2 + -1*y \<up> 2) + y/(x \<up> 2 + -1*x*y)";
   1.198 -val SOME (t', asm) = common_nominator_p_ thy t;
   1.199 -if UnparseC.term t' = 
   1.200 -  "x * x / ((x + - 1 * y) * ((x + y) * x)) +\ny * (x + y) / ((x + - 1 * y) * ((x + y) * x))"
   1.201 -then () else error "common_nominator_p_ term 2 changed"
   1.202 -;
   1.203 -if UnparseC.terms asm = "[\"x + y \<noteq> 0\", \"x \<noteq> 0\", \"x + - 1 * y \<noteq> 0\"]"
   1.204 -then () else error "common_nominator_p_ asm 2 changed"
   1.205 -
   1.206 -"-------- example: applicable tested by SML code";
   1.207 -val t = TermC.str2term "nothing / to_add";
   1.208 -if NONE = common_nominator_p_ thy t then () else error "common_nominator_p_ term 3 changed";
   1.209 -;
   1.210 -val t = TermC.str2term "((x + (-1)) / (x + 1)) + ((x + 1) / (x + (-1)))";
   1.211 -val SOME (t', asm) = common_nominator_p_ thy t;
   1.212 -if UnparseC.term t' = 
   1.213 -  "(x + - 1) * (- 1 + x) / ((1 + x) * (- 1 + x)) +\n(x + 1) * (1 + x) / ((1 + x) * (- 1 + x))"
   1.214 -  andalso UnparseC.terms asm = "[\"1 + x \<noteq> 0\", \"- 1 + x \<noteq> 0\"]"
   1.215 -then () else error "common_nominator_p_ 3 changed";
   1.216 -
   1.217 -"-------- integration lev.1 fun add_fraction_p_ ------------------------------";
   1.218 -"-------- integration lev.1 fun add_fraction_p_ ------------------------------";
   1.219 -"-------- integration lev.1 fun add_fraction_p_ ------------------------------";
   1.220 -val t = TermC.str2term "((x + (-1)) / (x + 1)) + ((x + 1) / (x + (-1)))";
   1.221 -val SOME (t', asm) = add_fraction_p_ thy t;
   1.222 -if UnparseC.term t' = "(2 + 2 * x \<up> 2) / (- 1 + x \<up> 2)" 
   1.223 -then () else error "add_fraction_p_ 3 changed";
   1.224 -;
   1.225 -if UnparseC.terms asm = "[\"- 1 + x \<up> 2 \<noteq> 0\"]"
   1.226 -then () else error "add_fraction_p_ 3 changed";
   1.227 -;
   1.228 -val t = TermC.str2term "nothing / to_add";
   1.229 -if NONE = add_fraction_p_ thy t then () else error "add_fraction_p_ term 3 changed";
   1.230 -;
   1.231 -val t = TermC.str2term "((x + (-1)) / (x + 1)) + ((x + 1) / (x + (-1)))";
   1.232 -val SOME (t', asm) = add_fraction_p_ thy t;
   1.233 -if UnparseC.term t' = "(2 + 2 * x \<up> 2) / (- 1 + x \<up> 2)" andalso
   1.234 -  UnparseC.terms asm = "[\"- 1 + x \<up> 2 \<noteq> 0\"]"
   1.235 -then () else error "add_fraction_p_ 3 changed";
   1.236 -
   1.237 -"-------- and app_rev ...traced down from rewrite_set_ until prepats ---------";
   1.238 -"-------- and app_rev ...traced down from rewrite_set_ until prepats ---------";
   1.239 -"-------- and app_rev ...traced down from rewrite_set_ until prepats ---------";
   1.240 -(* trace down until prepats are evaluated 
   1.241 -  (which does not to work, because substitution is not done -- compare rew_sub!);
   1.242 -  keep this sequence for the case, factout_p, cancel_p, common_nominator_p, add_fraction_p
   1.243 -  (again) get prepat = [] changed to <>[]. *)
   1.244 -val t = TermC.str2term "(x \<up> 2 + -1*y \<up> 2) / (x \<up> 2 + -1*x*y)";
   1.245 -
   1.246 -(*rewrite_set_ @{theory Isac_Knowledge} true cancel t = NONE; !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!*)
   1.247 -"~~~~~ fun rewrite_set_, args:"; val (thy, bool, rls, term) = (thy, false, cancel_p, t);
   1.248 -"~~~~~ fun rewrite__set_, args:"; val (thy, i, _, _, (rrls as Rrls _), t) =
   1.249 -  (thy, 1, bool, [], rls, term);
   1.250 -(*val (t', asm, rew) = app_rev thy (i+1) rrls t; rew = false!!!!!!!!!!!!!!!!!!!!!*)
   1.251 -"~~~~~ and app_rev, args:"; val (thy, i, rrls, t) = (thy, (i+1), rrls, t);
   1.252 -    fun chk_prepat thy erls [] t = true
   1.253 -      | chk_prepat thy erls prepat t =
   1.254 -        let
   1.255 -          fun chk (pres, pat) =
   1.256 -            (let 
   1.257 -              val subst: Type.tyenv * Envir.tenv =
   1.258 -                Pattern.match thy (pat, t) (Vartab.empty, Vartab.empty)
   1.259 -             in
   1.260 -              snd (eval__true thy (i + 1) (map (Envir.subst_term subst) pres) [] erls)
   1.261 -             end) handle Pattern.MATCH => false
   1.262 -           fun scan_ f [] = false (*scan_ NEVER called by []*)
   1.263 -             | scan_ f (pp::pps) =
   1.264 -               if f pp then true else scan_ f pps;
   1.265 -        in scan_ chk prepat end;
   1.266 -    (* apply the normal_form of a rev-set *)
   1.267 -    fun app_rev' thy (Rrls{erls,prepat,scr=Rfuns{normal_form,...},...}) t =
   1.268 -      if chk_prepat thy erls prepat t
   1.269 -      then ((*tracing("### app_rev': t = "^UnparseC.term t);*) normal_form t)
   1.270 -      else NONE;
   1.271 -(*  val opt = app_rev' thy rrls t  ..NONE!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!*)
   1.272 -"~~~~~ and app_rev', args:"; val (thy, (Rrls{erls,prepat,scr=Rfuns{normal_form,...},...}), t) =
   1.273 -  (thy, rrls, t);
   1.274 -(* chk_prepat thy erls prepat t = false!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!*)
   1.275 -(* app_sub thy i rrls t = false!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!*)
   1.276 -"~~~~~ fun chk_prepat, args:"; val (thy, erls, prepat, t) = (thy, erls, prepat, t);
   1.277 -          fun chk (pres, pat) =
   1.278 -            (let 
   1.279 -              val subst: Type.tyenv * Envir.tenv =
   1.280 -                Pattern.match thy (pat, t) (Vartab.empty, Vartab.empty)
   1.281 -             in
   1.282 -              snd (eval__true thy (i + 1) (map (Envir.subst_term subst) pres) [] erls)
   1.283 -             end) handle Pattern.MATCH => false
   1.284 -           fun scan_ f [] = false (*scan_ NEVER called by []*)
   1.285 -             | scan_ f (pp::pps) =
   1.286 -               if f pp then true else scan_ f pps;
   1.287 -
   1.288 -(*========== inhibit exn WN130823: prepat is empty ====================================
   1.289 -(* scan_ chk prepat = false!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!*)
   1.290 -"~~~~~ fun , args:"; val (f, (pp::pps)) = (chk, prepat);
   1.291 -f;
   1.292 -val ([t1, t2], t) = pp;
   1.293 -UnparseC.term t1 = "?r is_expanded";
   1.294 -UnparseC.term t2 = "?s is_expanded";
   1.295 -UnparseC.term t = "?r / ?s";
   1.296 -(* f pp = false!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!*)
   1.297 -"~~~~~ fun chk, args:"; val (pres, pat) = (pp);
   1.298 -              val subst: Type.tyenv * Envir.tenv =
   1.299 -                Pattern.match thy (pat, t) (Vartab.empty, Vartab.empty)
   1.300 -(*subst = 
   1.301 -  ({}, {(("r", 0), ("real", Var (("r", 0), "real"))), 
   1.302 -        (("s", 0), ("real", Var (("s", 0), "real")))}*)
   1.303 -;
   1.304 -              snd (eval__true thy (i + 1) (map (Envir.subst_term subst) pres) [] erls)
   1.305 -"~~~~~ fun eval__true, args:"; val (thy, i, asms, bdv, rls) =
   1.306 -  (thy, (i + 1), (map (Envir.subst_term subst) pres), [], erls);
   1.307 -UnparseC.terms asms;                         (* = "[\"?r is_expanded\",\"?s is_expanded\"]"*)
   1.308 -asms = [@{term True}] orelse asms = []; (* = false*)
   1.309 -asms = [@{term False}]                ; (* = false*)
   1.310 -"~~~~~ fun chk, args:"; val (indets, (a::asms)) = ([], asms);
   1.311 -bdv (*= []: _a list*);
   1.312 -val bdv : (term * term) list = [];
   1.313 -rewrite__set_ thy (i+1) false;
   1.314 -UnparseC.term a = "?r is_expanded"; (*hier m"usste doch der Numerator eingesetzt sein ??????????????*)
   1.315 -val SOME (Const ("HOL.False", _), []) = rewrite__set_ thy (i+1) false bdv rls a
   1.316 -============ inhibit exn WN130823: prepat is empty ===================================*)
   1.317 -
   1.318 -"-------- fun rewrite_set_ cancel_p downto fun gcd_poly ----------------------";
   1.319 -"-------- fun rewrite_set_ cancel_p downto fun gcd_poly ----------------------";
   1.320 -"-------- fun rewrite_set_ cancel_p downto fun gcd_poly ----------------------";
   1.321 -val t = TermC.str2term "(12 * x * y) / (8 * y \<up> 2 )";
   1.322 -(* "-------- example 187a": exception Div raised...
   1.323 -val SOME (t', asm) = rewrite_set_ thy false cancel_p t;*)
   1.324 -val t = TermC.str2term "(8 * x \<up> 2 * y * z ) / (18 * x * y \<up> 2 * z )";
   1.325 -(* "-------- example 187b": doesn't terminate...
   1.326 -val SOME (t', asm) = rewrite_set_ thy false cancel_p t;*)
   1.327 -val t = TermC.str2term "(9 * x \<up> 5 * y \<up> 2 * z \<up> 4) / (15 * x \<up> 6 * y \<up> 3 * z )";
   1.328 -(* "-------- example 187c": doesn't terminate...
   1.329 -val SOME (t', asm) = rewrite_set_ thy false cancel_p t;*)
   1.330 -"~~~~~ fun rewrite_set_, args:"; val (thy, bool, rls, term) = (@{theory Isac_Knowledge}, false, cancel_p, t);
   1.331 -(* WN130827: exception Div raised...
   1.332 -rewrite__set_ thy 1 bool [] rls term
   1.333 -*)
   1.334 -"~~~~~ and rewrite__set_, args:"; val (thy, i, _, _, (rrls as Rrls _), t) =
   1.335 -  (thy, 1, bool, [], rls, term);
   1.336 -(* WN130827: exception Div raised...
   1.337 -	val (t', asm, rew) = app_rev thy (i+1) rrls t
   1.338 -*)
   1.339 -"~~~~~ fun app_rev, args:"; val (thy, i, rrls, t) = (thy, (i+1), rrls, t);
   1.340 -(* WN130827: exception Div raised...
   1.341 -    val opt = app_rev' thy rrls t
   1.342 -*)
   1.343 -"~~~~~ fun app_rev', args:"; val (thy, (Rrls{erls,prepat,scr=Rfuns{normal_form,...},...}), t) =
   1.344 -  (thy, rrls, t);
   1.345 -chk_prepat thy erls prepat t    = true;
   1.346 -(* WN130827: exception Div raised...
   1.347 -normal_form t
   1.348 -*)
   1.349 -(* lookup Rational.thy, cancel_p: normal_form = cancel_p_ thy*)
   1.350 -"~~~~~ fun cancel_p_, args:"; val (t) = (t);
   1.351 -val opt = check_fraction t;
   1.352 -val SOME (numerator, denominator) = opt
   1.353 -        val vs = TermC.vars_of t
   1.354 -        val baseT = type_of numerator
   1.355 -        val expT = HOLogic.realT
   1.356 -val (SOME a, SOME b) = (poly_of_term vs numerator, poly_of_term vs denominator);
   1.357 -(*"-------- example 187a": exception Div raised...
   1.358 -val a = [(12, [1, 1])]: poly
   1.359 -val b = [(8, [0, 2])]: poly
   1.360 -              val ((a', b'), c) = gcd_poly a b
   1.361 -*)
   1.362 -(* "-------- example 187b": doesn't terminate...
   1.363 -val a = [(8, [2, 1, 1])]: poly
   1.364 -val b = [(18, [1, 2, 1])]: poly
   1.365 -              val ((a', b'), c) = gcd_poly a b
   1.366 -*)
   1.367 -(* "-------- example 187c": doesn't terminate...
   1.368 -val a = [(9, [5, 2, 4])]: poly
   1.369 -val b = [(15, [6, 3, 1])]: poly
   1.370 -              val ((a', b'), c) = gcd_poly a b
   1.371 -*)
   1.372 -
   1.373 -"-------- rls norm_Rational downto fun gcd_poly ------------------------------";
   1.374 -"-------- rls norm_Rational downto fun gcd_poly ------------------------------";
   1.375 -"-------- rls norm_Rational downto fun gcd_poly ------------------------------";
   1.376 -val t = TermC.str2term "(x \<up> 2 - 4)*(3 - y) / ((y \<up> 2 - 9)*(2+x))";
   1.377 -Rewrite.trace_on := false (*true false*);
   1.378 -(* trace stops with ...: (and then jEdit hangs)..
   1.379 -rewrite_set_ thy false norm_Rational t;
   1.380 -:
   1.381 -###  rls: cancel_p on: (-12 + 4 * y + 3 * x \<up> 2 + -1 * (x \<up> 2 * y)) /
   1.382 -(-18 + -9 * x + 2 * y \<up> 2 + x * y \<up> 2)
   1.383 -*)
   1.384 -val t = TermC.str2term (*copy from above: "::real" is not required due to " \<up> "*)
   1.385 -  ("(-12 + 4 * y + 3 * x \<up> 2 + -1 * (x \<up> 2 * y)) /" ^
   1.386 -  "(-18 + -9 * x + 2 * y \<up> 2 + x * y \<up> 2)");
   1.387 -(*cancel_p_ thy t;
   1.388 -exception Div raised*)
   1.389 -
   1.390 -"~~~~~ fun cancel_p_, args:"; val (t) = (t);
   1.391 -val opt = check_fraction t;
   1.392 -val SOME (numerator, denominator) = opt
   1.393 -        val vs = TermC.vars_of t
   1.394 -        val baseT = type_of numerator
   1.395 -        val expT = HOLogic.realT;
   1.396 -(*default_print_depth 3; 999*)
   1.397 -val (SOME a, SOME b) = (poly_of_term vs numerator, poly_of_term vs denominator);
   1.398 -(*default_print_depth 3; 999*)
   1.399 -(* does not terminate instead of returning ?:
   1.400 -        val ((a', b'), c) = gcd_poly a b
   1.401 -val a = [(~12, [0, 0]), (3, [2, 0]), (4, [0, 1]), (~1, [2, 1])]: poly
   1.402 -val b = [(~18, [0, 0]), (~9, [1, 0]), (2, [0, 2]), (1, [1, 2])]: poly
   1.403 -*)
   1.404 -
   1.405 -"-------- rls norm_Rational downto fun add_fraction_p_ -----------------------";
   1.406 -"-------- rls norm_Rational downto fun add_fraction_p_ -----------------------";
   1.407 -"-------- rls norm_Rational downto fun add_fraction_p_ -----------------------";
   1.408 -val thy =  @{theory Isac_Knowledge};
   1.409 -"----- SK060904-2a non-termination of add_fraction_p_";
   1.410 -val t = TermC.str2term (" (a + b * x) / (a + -1 * (b * x)) +  " ^
   1.411 -		         " (-1 * a + b * x) / (a + b * x)      ");
   1.412 -(* rewrite_set_ thy false norm_Rational t
   1.413 -exception Div raised*)
   1.414 -(* rewrite_set_ thy false add_fractions_p t;
   1.415 -exception Div raised*)
   1.416 -"~~~~~ fun rewrite_set_, args:"; val (thy, bool, rls, term) =
   1.417 -  (@{theory Isac_Knowledge}, false, add_fractions_p, t);
   1.418 -"~~~~~ and rewrite__set_, args:"; val (thy, i, _, _, (rrls as Rrls _), t) =
   1.419 -  (thy, 1, bool, [], rls, term);
   1.420 -(* app_rev thy (i+1) rrls t;
   1.421 -exception Div raised*)
   1.422 -"~~~~~ and app_rev, args:"; val (thy, i, rrls, t) = (thy, (i+1), rrls, t);
   1.423 -    fun chk_prepat thy erls [] t = true
   1.424 -      | chk_prepat thy erls prepat t =
   1.425 -        let
   1.426 -          fun chk (pres, pat) =
   1.427 -            (let 
   1.428 -              val subst: Type.tyenv * Envir.tenv =
   1.429 -                Pattern.match thy (pat, t) (Vartab.empty, Vartab.empty)
   1.430 -             in
   1.431 -              snd (eval__true thy (i + 1) (map (Envir.subst_term subst) pres) [] erls)
   1.432 -             end) handle Pattern.MATCH => false
   1.433 -           fun scan_ f [] = false (*scan_ NEVER called by []*)
   1.434 -             | scan_ f (pp::pps) =
   1.435 -               if f pp then true else scan_ f pps;
   1.436 -        in scan_ chk prepat end;
   1.437 -    (* apply the normal_form of a rev-set *)
   1.438 -    fun app_rev' thy (Rrls{erls,prepat,scr=Rfuns{normal_form,...},...}) t =
   1.439 -      if chk_prepat thy erls prepat t
   1.440 -      then ((*tracing("### app_rev': t = "^UnparseC.term t);*) normal_form t)
   1.441 -      else NONE;
   1.442 -(*  val opt = app_rev' thy rrls t;
   1.443 -exception Div raised*)
   1.444 -(*  val opt = app_rev' thy rrls t;
   1.445 -exception Div raised*)
   1.446 -"~~~~~ and app_rev', args:"; val (thy, (Rrls{erls,prepat,scr=Rfuns{normal_form,...},...}), t) =
   1.447 -  (thy, rrls, t);
   1.448 -chk_prepat thy erls prepat t = true       = true;
   1.449 -(*normal_form t
   1.450 -exception Div raised*)
   1.451 -(* lookup Rational.thy, val add_fractions_p: normal_form = add_fraction_p_ thy*)
   1.452 -(*add_fraction_p_ thy t
   1.453 -exception Div raised*)
   1.454 -"~~~~~ fun add_fraction_p_, args:"; val ((_: theory), t) = (thy, t);
   1.455 -val SOME ((n1, d1), (n2, d2)) = check_frac_sum t;
   1.456 -UnparseC.term n1; UnparseC.term d1; UnparseC.term n2; UnparseC.term d2;
   1.457 -      val vs = TermC.vars_of t;
   1.458 -(*default_print_depth 3; 999*)
   1.459 -val (SOME _, SOME a, SOME _, SOME b) =
   1.460 -  (poly_of_term vs n1, poly_of_term vs d1, poly_of_term vs n2, poly_of_term vs d2);
   1.461 -(*default_print_depth 3; 999*)
   1.462 -(*
   1.463 -val a = [(1, [1, 0, 0]), (~1, [0, 1, 1])]: poly
   1.464 -val b = [(1, [1, 0, 0]), (1, [0, 1, 1])]: poly
   1.465 -            val ((a', b'), c) = gcd_poly a b
   1.466 -*)
   1.467 -
   1.468 -"----------- fun check_frac_sum with Free A and Const AA ---------------------------------------";
   1.469 -"----------- fun check_frac_sum with Free A and Const AA ---------------------------------------";
   1.470 -"----------- fun check_frac_sum with Free A and Const AA ---------------------------------------";
   1.471 -val thy = @{theory Isac_Knowledge(*Partial_Fractions*)}
   1.472 -val ctxt = Proof_Context.init_global thy;
   1.473 -
   1.474 -(*---------- (1) with Free A, B  ----------------------------------------------------------------*)
   1.475 -val t = (the o (parseNEW  ctxt)) "3 = A / 2 + A / 4 + (B / 2 + -1 * B / (2::real))";
   1.476 -                                (* required for applying thms in rewriting  \<up> ^*)
   1.477 -(* we get details from here..*)
   1.478 -
   1.479 -Rewrite.trace_on := false;
   1.480 -val SOME (t', _) = Rewrite.rewrite_set_ thy true add_fractions_p t;
   1.481 -Rewrite.trace_on := false;
   1.482 -(* Rewrite.trace_on:
   1.483 -add_fractions_p on: 3 = A / 2 + A / 4 + (B / 2 + -1 * B / 2) --> 3 = A / 2 + A / 4 + 0 / 2 *)
   1.484 -                     (* |||||||||||||||||||||||||||||||||||| *)
   1.485 -
   1.486 -val t = (the o (parseNEW  ctxt))(* ||||||||||||||||||||||||| GUESS 1 GUESS 1 GUESS 1 GUESS 1 *)
   1.487 -                       "A / 2 + A / 4 + (B / 2 + -1 * B / (2::real))";
   1.488 -"~~~~~ fun add_fraction_p_ , ad-hoc args:"; val (t) = (t);
   1.489 -val NONE = (*case*) check_frac_sum t (*of*)
   1.490 -
   1.491 -(* Rewrite.trace_on:
   1.492 -add_fractions_p on: 3 = A / 2 + A / 4 + (B / 2 + -1 * B / 2) --> 3 = A / 2 + A / 4 + 0 / 2 *)
   1.493 -                     (*         |||||||||||||||||||||||||||| *)
   1.494 -val t = (the o (parseNEW  ctxt))(* ||||||||||||||||||||||||| GUESS 2 GUESS 2 GUESS 2 GUESS 2 *)
   1.495 -                               "A / 4 + (B / 2 + -1 * B / (2::real))";
   1.496 -"~~~~~ fun add_fraction_p_ , ad-hoc args:"; val (t) = (t);
   1.497 -val SOME ((n1, d1), (n2, d2)) = (*case*) check_frac_sum t (*of*);
   1.498 -(*+*)if (UnparseC.term n1, UnparseC.term d1) = ("A"                 , "4") andalso
   1.499 -(*+*)   (UnparseC.term n2, UnparseC.term d2) = ("B / 2 + - 1 * B / 2", "1")
   1.500 -(*+*)then () else error "check_frac_sum (A / 4 + (B / 2 + -1 * B / (2::real))) changed";
   1.501 -
   1.502 -      val vs = TermC.vars_of t;
   1.503 -val (SOME [(1, [1, 0])], SOME [(4, [0, 0])], NONE, SOME [(1, [0, 0])]) =
   1.504 -  (*case*) (poly_of_term vs n1, poly_of_term vs d1, poly_of_term vs n2, poly_of_term vs d2) (*of*);
   1.505 -
   1.506 -"~~~~~ fun poly_of_term , args:"; val (vs, t) = (vs, n1);
   1.507 -val SOME [(1, [xxx, 0])] = SOME [monom_of_term vs (1, replicate (length vs) 0) t];
   1.508 -(*+*)if xxx = 1 then () else error "monom_of_term changed"
   1.509 -
   1.510 -"~~~~~ fun monom_of_term , args:"; val (vs, (c, es), (Free (id, _))) =
   1.511 -  (vs, (1, replicate (length vs) 0), t);
   1.512 -case vs of [Free ("A", _), Free ("B", _)] =>
   1.513 -  if c = 1 andalso id = "A"
   1.514 -  then () else error "monom_of_term Free changed 1"
   1.515 -| _ => error "monom_of_term Free changed 2";
   1.516 -
   1.517 -(*---------- (2) with Const AA, BB --------------------------------------------------------------*)
   1.518 -val t = (the o (parseNEW  ctxt)) "3 = AA / 2 + AA / 4 + (BB / 2 + -1 * BB / 2)";
   1.519 -                                    (*AA :: real*)
   1.520 -(* we get details from here..*)
   1.521 -
   1.522 -Rewrite.trace_on := false;
   1.523 -val SOME (t', _) = Rewrite.rewrite_set_ thy true add_fractions_p t;
   1.524 -Rewrite.trace_on := false;
   1.525 -(* Rewrite.trace_on:
   1.526 -add_fractions_p on: 3 = A / 2 + A / 4 + (B / 2 + -1 * B / 2) --> 3 = A / 2 + A / 4 + 0 / 2 *)
   1.527 -                     (* |||||||||||||||||||||||||||||||||||| *)
   1.528 -val t = (the o (parseNEW  ctxt))(* ||||||||||||||||||||||||| *)
   1.529 -                   "AA / 2 + AA / 4 + (BB / 2 + -1 * BB / 2)";
   1.530 -"~~~~~ fun add_fraction_p_ , ad-hoc args:"; val (t) = (t);
   1.531 -val NONE = (*case*) check_frac_sum t (*of*)
   1.532 -
   1.533 -(* Rewrite.trace_on:
   1.534 -add_fractions_p on: 3 = A / 2 + A / 4 + (B / 2 + -1 * B / 2) --> 3 = A / 2 + A / 4 + 0 / 2 *)
   1.535 -                     (*         |||||||||||||||||||||||||||| *)
   1.536 -val t = (the o (parseNEW  ctxt))(* ||||||||||||||||||||||||| *)
   1.537 -                               "AA / 4 + (BB / 2 + -1 * BB / 2)";
   1.538 -"~~~~~ fun add_fraction_p_ , ad-hoc args:"; val (t) = (t);
   1.539 -val SOME ((n1, d1), (n2, d2)) = (*case*) check_frac_sum t (*of*);
   1.540 -(*+*)if (UnparseC.term n1, UnparseC.term d1) = ("AA"                 , "4") andalso
   1.541 -(*+*)   (UnparseC.term n2, UnparseC.term d2) = ("BB / 2 + - 1 * BB / 2", "1")
   1.542 -(*+*)then () else error "check_frac_sum (AA / 4 + (BB / 2 + -1 * BB / 2)) changed";
   1.543 -
   1.544 -      val vs = TermC.vars_of t;
   1.545 -val (SOME [(1, [1, 0])], SOME [(4, [0, 0])], NONE, SOME [(1, [0, 0])]) =
   1.546 -  (*case*) (poly_of_term vs n1, poly_of_term vs d1, poly_of_term vs n2, poly_of_term vs d2) (*of*);
   1.547 -
   1.548 -"~~~~~ fun poly_of_term , args:"; val (vs, t) = (vs, n1);
   1.549 -val SOME [(1, [xxx, 0])] = SOME [monom_of_term vs (1, replicate (length vs) 0) t];
   1.550 -(*+*)if xxx = 1 then () else error "monom_of_term changed"
   1.551 -
   1.552 -"~~~~~ fun monom_of_term , args:"; val (vs, (c, es), (Const (id, _))) =
   1.553 -  (vs, (1, replicate (length vs) 0), t);
   1.554 -case vs of [Const ("Partial_Fractions.AA", _), Const ("Partial_Fractions.BB", _)] =>
   1.555 -  if c = 1 andalso id = "Partial_Fractions.AA"
   1.556 -  then () else error "monom_of_term Const changed 1"
   1.557 -| _ => error "monom_of_term Const changed 2";
   1.558 -
   1.559 -"----------- fun cancel_p with Const AA --------------------------------------------------------";
   1.560 -"----------- fun cancel_p with Const AA --------------------------------------------------------";
   1.561 -"----------- fun cancel_p with Const AA --------------------------------------------------------";
   1.562 -val thy = @{theory Partial_Fractions};
   1.563 -val ctxt = Proof_Context.init_global @{theory}
   1.564 -val SOME t = TermC.parseNEW ctxt "2 * AA / 2"; (* Const ("Free ("AA", "real") *)
   1.565 -
   1.566 -val SOME (t', _) = rewrite_set_ thy true cancel_p t;
   1.567 -case t' of
   1.568 -  Const ("Rings.divide_class.divide", _) $ Const ("Partial_Fractions.AA", _) $
   1.569 -    Const ("Groups.one_class.one", _) => ()
   1.570 -| _ => error "WRONG rewrite_set_ cancel_p (2 * AA / 2) \<longrightarrow> AA changed";
   1.571 -
   1.572 -"~~~~~ fun cancel_p , args:"; val (t) = (t);
   1.573 -val opt = check_fraction t
   1.574 -val SOME (numerator, denominator) = (*case*) opt (*of*);
   1.575 -
   1.576 -if UnparseC.term numerator = "2 * AA" andalso UnparseC.term denominator = "2"
   1.577 -then () else error "check_fraction (2 * AA / 2) changed";
   1.578 -        val vs = TermC.vars_of t;
   1.579 -case vs of
   1.580 -  [Const ("Partial_Fractions.AA", _)] => ()
   1.581 -| _ => error "rewrite_set_ cancel_p (2 * AA / 2) \<longrightarrow> AA/1  changed";
   1.582 -
   1.583 -
   1.584 -"-------- rewrite_set_ cancel_p from: Mathematik 1 Schalk Reniets Verlag -----";
   1.585 -"-------- rewrite_set_ cancel_p from: Mathematik 1 Schalk Reniets Verlag -----";
   1.586 -"-------- rewrite_set_ cancel_p from: Mathematik 1 Schalk Reniets Verlag -----";
   1.587 -val thy  = @{theory "Rational"};
   1.588 -"-------- WN";
   1.589 -val t = TermC.str2term "(2 + -3 * x) / 9";
   1.590 -if NONE = rewrite_set_ thy false cancel_p t then ()
   1.591 -else error "rewrite_set_ cancel_p must return NONE, if the term cannot be cancelled";
   1.592 -
   1.593 -"-------- example 186a";
   1.594 -val t = TermC.str2term "(14 * x * y) / (x * y)";
   1.595 -  is_expanded (TermC.str2term "14 * x * y");
   1.596 -  is_expanded (TermC.str2term "x * y");
   1.597 -val SOME (t', asm) = rewrite_set_ thy false cancel_p t;
   1.598 -if (UnparseC.term t', UnparseC.terms asm) = ("14 / 1", "[]")
   1.599 -then () else error "rational.sml cancel Schalk 186a";
   1.600 -
   1.601 -"-------- example 186b";
   1.602 -val t = TermC.str2term "(60 * a * b) / ( 15 * a  * b )";
   1.603 -val SOME (t', asm) = rewrite_set_ thy false cancel_p t;
   1.604 -if (UnparseC.term t', UnparseC.terms asm) = ("4 / 1", "[]")
   1.605 -then () else error "rational.sml cancel Schalk 186b";
   1.606 -
   1.607 -"-------- example 186c";
   1.608 -val t = TermC.str2term "(144 * a \<up> 2 * b * c) / (12 * a * b * c)";
   1.609 -val SOME (t', asm) = rewrite_set_ thy false cancel_p t;
   1.610 -if (UnparseC.term t', UnparseC.terms asm) = ("12 * a / 1", "[]")
   1.611 -then () else error "rational.sml cancel Schalk 186c";
   1.612 -
   1.613 -(* !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! exception Div raised !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
   1.614 -  see --- fun rewrite_set_ downto fun gcd_poly ---
   1.615 -"-------- example 187a";
   1.616 -val t = TermC.str2term "(12 * x * y) / (8 * y \<up> 2 )";
   1.617 -val SOME (t', asm) = rewrite_set_ thy false cancel_p t;
   1.618 -if (UnparseC.term t', UnparseC.terms asm) = ("3 * x / (2 * y)", "[\"4 * y ~= 0\"]")
   1.619 -then () else error "rational.sml cancel Schalk 187a";
   1.620 -*)
   1.621 -
   1.622 -(* doesn't terminate !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
   1.623 -  see --- fun rewrite_set_ downto fun gcd_poly ---
   1.624 -"-------- example 187b";
   1.625 -val t = TermC.str2term "(8 * x \<up> 2 * y * z ) / (18 * x * y \<up> 2 * z )";
   1.626 -val SOME (t', asm) = rewrite_set_ thy false cancel_p t;
   1.627 -if (UnparseC.term t', UnparseC.terms asm) = ("4 * x / (9 * y)", "[\"2 * (z * (y * x)) ~= 0\"]")
   1.628 -then () else error "rational.sml cancel Schalk 187b";
   1.629 -*)
   1.630 -
   1.631 -(* doesn't terminate !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
   1.632 -  see --- fun rewrite_set_ downto fun gcd_poly ---
   1.633 -"-------- example 187c";
   1.634 -val t = TermC.str2term "(9 * x \<up> 5 * y \<up> 2 * z \<up> 4) / (15 * x \<up> 6 * y \<up> 3 * z )";
   1.635 -val SOME (t', asm) = rewrite_set_ thy false cancel_p t;
   1.636 -if (UnparseC.term t', UnparseC.terms asm) = 
   1.637 -  ("3 * z \<up> 3 / (5 * (y * x))", "[\"3 * (z * (y \<up> 2 * x \<up> 5)) ~= 0\"]") 
   1.638 -then () else error "rational.sml cancel Schalk 187c";
   1.639 -*)
   1.640 -
   1.641 -"-------- example 188a";
   1.642 -val t = TermC.str2term "(-8 + 8 * x) / (-9 + 9 * x)";
   1.643 -  is_expanded (TermC.str2term "8 * x + -8");
   1.644 -val SOME (t', asm) = rewrite_set_ thy false cancel_p t;
   1.645 -if (UnparseC.term t', UnparseC.terms asm) = ("8 / 9", "[]")
   1.646 -then () else error "rational.sml cancel Schalk 188a";
   1.647 -
   1.648 -val t = TermC.str2term "(8*((-1) + x))/(9*((-1) + x))";
   1.649 -val SOME (t, _) = rewrite_set_ thy false make_polynomial t;
   1.650 -if (UnparseC.term t', UnparseC.terms asm) = ("8 / 9", "[]")
   1.651 -then () else error "rational.sml cancel Schalk make_polynomial 1";
   1.652 -
   1.653 -"-------- example 188b";
   1.654 -val t = TermC.str2term "(-15 + 5 * x) / (-18 + 6 * x)";
   1.655 -val SOME (t', asm) = rewrite_set_ thy false cancel_p t;
   1.656 -if (UnparseC.term t', UnparseC.terms asm) = ("5 / 6", "[]")
   1.657 -then () else error "rational.sml cancel Schalk 188b";
   1.658 -
   1.659 -"-------- example 188c";
   1.660 -val t = TermC.str2term "(a + -1 * b) / (b + -1 * a)";
   1.661 -val SOME (t', asm) = rewrite_set_ thy false  cancel_p t;
   1.662 -if (UnparseC.term t', UnparseC.terms asm) = ("- 1 / 1", "[]")
   1.663 -then () else error "rational.sml cancel Schalk 188c";
   1.664 -
   1.665 -is_expanded (TermC.str2term "a + -1 * b") = true;
   1.666 -val t = TermC.str2term "((- 1)*(b + (-1) * a))/(1*(b + (- 1) * a))";
   1.667 -val SOME (t', asm) = rewrite_set_ thy false make_polynomial t;
   1.668 -if (UnparseC.term t', UnparseC.terms asm) = ("(a + - 1 * b) / (- 1 * a + b)", "[]")
   1.669 -then () else error "rational.sml cancel Schalk make_polynomial 2";
   1.670 -
   1.671 -"-------- example 190a";
   1.672 -val t = TermC.str2term "( 27 * a \<up> 3 + 9 * a \<up> 2 + 3 * a + 1 ) / ( 27 * a \<up> 3 + 18 * a \<up> 2 + 3 * a )";
   1.673 -val SOME (t', asm) = rewrite_set_ thy false cancel_p t;
   1.674 -if (UnparseC.term t', UnparseC.terms asm) = 
   1.675 -  ("(1 + 9 * a \<up> 2) / (3 * a + 9 * a \<up> 2)", "[\"3 * a + 9 * a \<up> 2 \<noteq> 0\"]")
   1.676 -then () else error "rational.sml cancel Schalk 190a";
   1.677 -
   1.678 -"-------- example 190c";
   1.679 -val t = TermC.str2term "((1 + 9 * a \<up> 2)*(1 + 3 * a))/((3 * a + 9 * a \<up> 2)*(1 + 3 * a))";
   1.680 -val SOME (t', asm) = rewrite_set_ thy false make_polynomial t;
   1.681 -if (UnparseC.term t', UnparseC.terms asm) = 
   1.682 -  ("(1 + 3 * a + 9 * a \<up> 2 + 27 * a \<up> 3) /\n(3 * a + 18 * a \<up> 2 + 27 * a \<up> 3)", "[]")
   1.683 -then () else error "rational.sml make_polynomial Schalk 190c";
   1.684 -
   1.685 -"-------- example 191a";
   1.686 -val t = TermC.str2term "( x \<up> 2 + -1 * y \<up> 2 ) / ( x + y )";
   1.687 -  is_expanded (TermC.str2term "x \<up> 2 + - 1 * y \<up> 2") = false; (*!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!*)
   1.688 -  is_expanded (TermC.str2term "x + y") = true;
   1.689 -val SOME (t', asm) = rewrite_set_ thy false cancel_p t;
   1.690 -if (UnparseC.term t', UnparseC.terms asm) = ("(x + - 1 * y) / 1", "[]")
   1.691 -then () else error "rational.sml make_polynomial Schalk 191a";
   1.692 -
   1.693 -"-------- example 191b";
   1.694 -val t = TermC.str2term "((x + (- 1) * y)*(x + y))/((1)*(x + y))";
   1.695 -val SOME (t', asm) = rewrite_set_ thy false make_polynomial t;
   1.696 -if (UnparseC.term t', UnparseC.terms asm) = ("(x \<up> 2 + - 1 * y \<up> 2) / (x + y)", "[]")
   1.697 -then () else error "rational.sml make_polynomial Schalk 191b";
   1.698 -
   1.699 -"-------- example 191c";
   1.700 -val t = TermC.str2term "( 9 * x \<up> 2 + -30 * x + 25 ) / ( 9 * x \<up> 2 + -25 )";
   1.701 -  is_expanded (TermC.str2term "9 * x \<up> 2 + -30 * x + 25") = true;
   1.702 -  is_expanded (TermC.str2term "25 + -30*x + 9*x \<up> 2") = true;
   1.703 -  is_expanded (TermC.str2term "-25 + 9*x \<up> 2") = true;
   1.704 -
   1.705 -val t = TermC.str2term "(((-5) + 3 * x)*((-5) + 3 * x))/((5 + 3 * x)*((-5) + 3 * x))";
   1.706 -val SOME (t', asm) = rewrite_set_ thy false make_polynomial t;
   1.707 -if (UnparseC.term t', UnparseC.terms asm) = ("(25 + - 30 * x + 9 * x \<up> 2) / (- 25 + 9 * x \<up> 2)", "[]")
   1.708 -then () else error "rational.sml make_polynomial Schalk 191c";
   1.709 -
   1.710 -"-------- example 192b";
   1.711 -val t = TermC.str2term "( 7 * x \<up> 3 + - 1 * x \<up> 2 * y ) / ( 7 * x * y \<up> 2 + - 1 *  y \<up> 3 )";
   1.712 -val SOME (t', asm) = rewrite_set_ thy false cancel_p t;
   1.713 -if (UnparseC.term t', UnparseC.terms asm) = ("x \<up> 2 / y \<up> 2", "[\"y \<up> 2 \<noteq> 0\"]")
   1.714 -then () else error "rational.sml cancel_p Schalk 192b";
   1.715 -
   1.716 -val t = TermC.str2term "((x \<up> 2)*(7 * x + (-1) * y))/((y \<up> 2)*(7 * x + (-1) * y))";
   1.717 -val SOME (t', asm) = rewrite_set_ thy false make_polynomial t;
   1.718 -if (UnparseC.term t', UnparseC.terms asm) = 
   1.719 -  ("(7 * x \<up> 3 + - 1 * x \<up> 2 * y) /\n(7 * x * y \<up> 2 + - 1 * y \<up> 3)", "[]")
   1.720 -then () else error "rational.sml make_polynomial Schalk 192b";
   1.721 -
   1.722 -val t = TermC.str2term "((x \<up> 2)*(7 * x + (-1) * y))/((y \<up> 2)*(7 * x + (-1) * y))";
   1.723 -val SOME (t', asm) = rewrite_set_ thy false make_polynomial t;
   1.724 -if (UnparseC.term t', UnparseC.terms asm) = 
   1.725 -  ("(7 * x \<up> 3 + - 1 * x \<up> 2 * y) /\n(7 * x * y \<up> 2 + - 1 * y \<up> 3)", "[]")
   1.726 -then () else error "rational.sml make_polynomial Schalk WN050929 not working";
   1.727 -
   1.728 -"-------- example 193a";
   1.729 -val t = TermC.str2term "( x \<up> 2 + -6 * x + 9 ) / ( x \<up> 2 + -9 )";
   1.730 -val SOME (t', asm) = rewrite_set_ thy false cancel_p t;
   1.731 -if (UnparseC.term t', UnparseC.terms asm) = ("(- 3 + x) / (3 + x)", "[\"3 + x \<noteq> 0\"]")
   1.732 -then () else error "rational.sml cancel_p Schalk 193a";
   1.733 -
   1.734 -"-------- example 193b";
   1.735 -val t = TermC.str2term "( x \<up> 2 + -8 * x + 16 ) / ( 2 * x \<up> 2 + -32 )";
   1.736 -val SOME (t', asm) = rewrite_set_ thy false cancel_p t;
   1.737 -if (UnparseC.term t', UnparseC.terms asm) = ("(- 4 + x) / (8 + 2 * x)", "[\"8 + 2 * x \<noteq> 0\"]")
   1.738 -then () else error "rational.sml cancel_p Schalk 193b";
   1.739 -
   1.740 -"-------- example 193c";
   1.741 -val t = TermC.str2term "( 2 * x + -50 * x \<up> 3 ) / ( 25 * x \<up> 2 + -10 * x + 1 )";
   1.742 -val SOME (t', asm) = rewrite_set_ thy false cancel_p t;
   1.743 -if (UnparseC.term t', UnparseC.terms asm) = 
   1.744 -  ("(2 * x + 10 * x \<up> 2) / (1 + - 5 * x)", "[\"1 + - 5 * x \<noteq> 0\"]")
   1.745 -then () else error "rational.sml cancel_p Schalk 193c";
   1.746 -
   1.747 -(*WN: improved with new numerals*)
   1.748 -val t = TermC.str2term "(-25 + 9*x \<up> 2)/(5 + 3*x)";
   1.749 -val SOME (t', asm) = rewrite_set_ thy false cancel_p t;
   1.750 -if (UnparseC.term t', UnparseC.terms asm) = ("(- 5 + 3 * x) / 1", "[]")
   1.751 -then () else error "rational.sml cancel WN 1";
   1.752 -
   1.753 -"-------- example heuberger";
   1.754 -val t = TermC.str2term ("(x \<up> 4 + x * y + x \<up> 3 * y + y \<up> 2) / " ^
   1.755 -  "(x + 5 * x \<up> 2 + y + 5 * x * y + x \<up> 2 * y \<up> 3 + x * y \<up> 4)");
   1.756 -val SOME (t', asm) = rewrite_set_ thy false cancel_p t;
   1.757 -if (UnparseC.term t', UnparseC.terms asm) = 
   1.758 -  ("(x \<up> 3 + y) / (1 + 5 * x + x * y \<up> 3)", "[\"1 + 5 * x + x * y \<up> 3 \<noteq> 0\"]")
   1.759 -then () else error "rational.sml cancel_p heuberger";
   1.760 -
   1.761 -"-------- rewrite_set_ add_fractions_p from: Mathematik 1 Schalk -------------";
   1.762 -"-------- rewrite_set_ add_fractions_p from: Mathematik 1 Schalk -------------";
   1.763 -"-------- rewrite_set_ add_fractions_p from: Mathematik 1 Schalk -------------";
   1.764 -(*deleted example 204 ... 236b at update Isabelle2012-->2013*)
   1.765 -
   1.766 -"-------- integration lev.1 -- lev.5: cancel_p_ & add_fractions_p_ -----------";
   1.767 -"-------- integration lev.1 -- lev.5: cancel_p_ & add_fractions_p_ -----------";
   1.768 -"-------- integration lev.1 -- lev.5: cancel_p_ & add_fractions_p_ -----------";
   1.769 -val t = TermC.str2term ("123 = (a*x)/(b*x) + (c*x)/(d*x) + (e*x)/(f*x::real)");
   1.770 -"-------- gcd_poly integration level 1: works on exact term";
   1.771 -if NONE = cancel_p_ thy t then () else error "cancel_p_ works on exact fraction";
   1.772 -if NONE = add_fraction_p_ thy t then () else error "add_fraction_p_ works on exact fraction";
   1.773 -
   1.774 -"-------- gcd_poly integration level 2: picks out ONE appropriate subterm";
   1.775 -val SOME (t', asm) = rewrite_set_ thy false cancel_p t;
   1.776 -if UnparseC.term t' = "123 = a * x / (b * x) + c * x / (d * x) + e / f" 
   1.777 -then () else error "level 2, rewrite_set_ cancel_p: changed";
   1.778 -val SOME (t', asm) = rewrite_set_ thy false add_fractions_p t;
   1.779 -if UnparseC.term t' = "123 = (b * c * x + a * d * x) / (b * d * x) + e * x / (f * x)"
   1.780 -then () else error "level 2, rewrite_set_ add_fractions_p: changed";
   1.781 -
   1.782 -"-------- gcd_poly integration level 3: rewrites all appropriate subterms";
   1.783 -val SOME (t', asm) = rewrite_set_ thy false cancel_p_rls t;
   1.784 -if UnparseC.term t' = "123 = a / b + c / d + e / f"
   1.785 -then () else error "level 3, rewrite_set_ cancel_p_rls: changed";
   1.786 -val SOME (t', asm) = rewrite_set_ thy false add_fractions_p_rls t; (*CREATE add_fractions_p_rls*)
   1.787 -if UnparseC.term t' = "123 = (b * d * e * x + b * c * f * x + a * d * f * x) / (b * d * f * x)"
   1.788 -then () else error "level 3, rewrite_set_ add_fractions_p_rls: changed";
   1.789 -
   1.790 -"-------- gcd_poly integration level 4: iteration cancel_p -- add_fraction_p";
   1.791 -(* simpler variant *)
   1.792 -val testrls = Rule_Set.append_rules "testrls" Rule_Set.empty [Rls_ cancel_p, Rls_ add_fractions_p]
   1.793 -val SOME (t', asm) = rewrite_set_ thy false testrls t;
   1.794 -(*Rewrite.trace_on := false;
   1.795 -#  rls: testrls on: 123 = a * x / (b * x) + c * x / (d * x) + e * x / (f * x) 
   1.796 -##  rls: cancel_p on: 123 = a * x / (b * x) + c * x / (d * x) + e * x / (f * x) 
   1.797 -##  rls: add_fractions_p on: 123 = a * x / (b * x) + c * x / (d * x) + e / f 
   1.798 -##  rls: cancel_p on: 123 = (b * c * x + a * d * x) / (b * d * x) + e / f 
   1.799 -##  rls: add_fractions_p on: 123 = (b * c + a * d) / (b * d) + e / f 
   1.800 -##  rls: cancel_p on: 123 = (b * d * e + b * c * f + a * d * f) / (b * d * f) 
   1.801 -##  rls: add_fractions_p on: 123 = (b * d * e + b * c * f + a * d * f) / (b * d * f) *)
   1.802 -if UnparseC.term t' = "123 = (b * d * e + b * c * f + a * d * f) / (b * d * f)"
   1.803 -then () else error "level 4, rewrite_set_ *_p: changed";
   1.804 -
   1.805 -(* complicated variant *)
   1.806 -val testrls_rls = Rule_Set.append_rules "testrls_rls" Rule_Set.empty [Rls_ cancel_p_rls, Rls_ add_fractions_p_rls];
   1.807 -val SOME (t', asm) = rewrite_set_ thy false testrls_rls t;
   1.808 -(*#  rls: testrls_rls on: 123 = a * x / (b * x) + c * x / (d * x) + e * x / (f * x) 
   1.809 -##  rls: cancel_p_rls on: 123 = a * x / (b * x) + c * x / (d * x) + e * x / (f * x) 
   1.810 -###  rls: cancel_p on: 123 = a * x / (b * x) + c * x / (d * x) + e * x / (f * x) 
   1.811 -###  rls: cancel_p on: 123 = a * x / (b * x) + c * x / (d * x) + e / f 
   1.812 -###  rls: cancel_p on: 123 = a * x / (b * x) + c / d + e / f 
   1.813 -###  rls: cancel_p on: 123 = a / b + c / d + e / f 
   1.814 -##  rls: add_fractions_p_rls on: 123 = a / b + c / d + e / f 
   1.815 -###  rls: add_fractions_p on: 123 = a / b + c / d + e / f 
   1.816 -###  rls: add_fractions_p on: 123 = (b * c + a * d) / (b * d) + e / f 
   1.817 -###  rls: add_fractions_p on: 123 = (b * d * e + b * c * f + a * d * f) / (b * d * f) 
   1.818 -##  rls: cancel_p_rls on: 123 = (b * d * e + b * c * f + a * d * f) / (b * d * f) 
   1.819 -###  rls: cancel_p on: 123 = (b * d * e + b * c * f + a * d * f) / (b * d * f) 
   1.820 -##  rls: add_fractions_p_rls on: 123 = (b * d * e + b * c * f + a * d * f) / (b * d * f) 
   1.821 -###  rls: add_fractions_p on: 123 = (b * d * e + b * c * f + a * d * f) / (b * d * f) *)
   1.822 -if UnparseC.term t' = "123 = (b * d * e + b * c * f + a * d * f) / (b * d * f)"
   1.823 -then () else error "level 4, rewrite_set_ *_p_rls: changed"
   1.824 -
   1.825 -"-------- gcd_poly integration level 5: cancel_p & add_fraction_p within norm_Rational";
   1.826 -val SOME (t', asm) = rewrite_set_ thy false norm_Rational t;
   1.827 -if UnparseC.term t' = "123 = (a * d * f + b * c * f + b * d * e) / (b * d * f)"
   1.828 -then () else error "level 5, rewrite_set_ norm_Rational: changed"
   1.829 -
   1.830 -"-------- reverse rewrite ----------------------------------------------------";
   1.831 -"-------- reverse rewrite ----------------------------------------------------";
   1.832 -"-------- reverse rewrite ----------------------------------------------------";
   1.833 -(** the term for which reverse rewriting is demonstrated **)
   1.834 -val t = TermC.str2term "(9 + -1 * x \<up> 2) / (9 + 6 * x + x \<up> 2)";
   1.835 -val Rrls {scr = Rfuns {init_state = ini, locate_rule = loc,
   1.836 -  next_rule = nex, normal_form = nor, ...},...} = cancel_p;
   1.837 -
   1.838 -(** normal_form produces the result in ONE step **)
   1.839 -  val SOME (t', _) = nor t;
   1.840 -if UnparseC.term t' = "(3 + - 1 * x) / (3 + x)" then ()
   1.841 -else error "rational.sml normal_form (9 - x \<up> 2) / (9 - 6 * x + x \<up> 2)";
   1.842 -
   1.843 -(** initialize the interpreter state used by the 'me' **)
   1.844 -  val (t, _, revsets, _) = ini t;
   1.845 -
   1.846 -if length (hd revsets) = 11 then () else error "length of revset changed";
   1.847 -(*//----------------------------------TOODOO (*Rfuns revsets \<longrightarrow> broken*)
   1.848 -if (revsets |> nth 1 |> nth 1 |> id_of_thm) = 
   1.849 -  (@{thm realpow_twoI} |> Thm.get_name_hint |> ThmC.cut_id)
   1.850 -then () else error "first element of revset changed";
   1.851 -if
   1.852 -(revsets |> nth 1 |> nth 1 |> Rule.to_string) = "Thm (\"realpow_twoI\",?r1 \<up> 2 = ?r1 * ?r1)" andalso
   1.853 -(revsets |> nth 1 |> nth 2 |> Rule.to_string) = "Thm (\"#: 9 = 3 \<up> 2\",9 = 3 \<up> 2)" andalso
   1.854 -(revsets |> nth 1 |> nth 3 |> Rule.to_string) = "Thm (\"#: 6 * x = 2 * (3 * x)\",6 * x = 2 * (3 * x))" 
   1.855 -andalso
   1.856 -(revsets |> nth 1 |> nth 4 |> Rule.to_string) = "Thm (\"#: -3 * x = -1 * (3 * x)\",-3 * x = -1 * (3 * x))" 
   1.857 -andalso
   1.858 -(revsets |> nth 1 |> nth 5 |> Rule.to_string) = "Thm (\"#: 9 = 3 * 3\",9 = 3 * 3)" andalso
   1.859 -(revsets |> nth 1 |> nth 6 |> Rule.to_string) = "Rls_ (\"sym_order_mult_rls_\")" andalso
   1.860 -(revsets |> nth 1 |> nth 7 |> Rule.to_string) = 
   1.861 -  "Thm (\"sym_mult.assoc\",?a * (?b * ?c) = ?a * ?b * ?c)"
   1.862 -then () else error "first 7 elements in revset changed"
   1.863 -  \\----------------------------------TOODOO (*Rfuns revsets \<longrightarrow> broken*)*)
   1.864 -
   1.865 -(** find the rule 'r' to apply to term 't' **)
   1.866 -(*/------- WN1309: since cancel_ (accepted "-" between monomials) has been replaced by cancel_p_ 
   1.867 -  for Isabelle2013, we don't get a working revset, but non-termination:
   1.868 -
   1.869 -  val SOME (r as (Thm (str, thm))) = nex revsets t;
   1.870 -  :
   1.871 -((3 * 3 + -1 * x * x) / (3 * 3 + 2 * 3 * x + x * x), 
   1.872 -  Rls_ ("sym_order_mult_rls_"), ((3 * 3 + -1 * (x * x)) / (3 * 3 + 2 * (3 * x) + x * x), []))", "
   1.873 -((3 * 3 + -1 * (x * x)) / (3 * 3 + 2 * (3 * x) + x * x), 
   1.874 -  Thm ("sym_mult.assoc", ""), ((3 * 3 + -1 * (x * x)) / (3 * 3 + 2 * 3 * x + x * x), []))", "
   1.875 -((3 * 3 + -1 * (x * x)) / (3 * 3 + 2 * 3 * x + x * x), 
   1.876 -  Thm ("sym_mult.assoc", ""), ((3 * 3 + -1 * x * x) / (3 * 3 + 2 * 3 * x + x * x), []))", "
   1.877 -((3 * 3 + -1 * x * x) / (3 * 3 + 2 * 3 * x + x * x), Rls_ ("sym_order_mult_rls_"), ((3 * 3 + -1 * (x * x)) / (3 * 3 + 2 * (3 * x) + x * x), []))", "
   1.878 - :
   1.879 -### Isabelle2002:
   1.880 -  Thm ("sym_#mult_2_3", "6 = 2 * 3")
   1.881 -### Isabelle2009-2 for cancel_ (not cancel_p_):
   1.882 -if str = "sym_#power_Float ((3,0), (0,0)) __ ((2,0), (0,0))"
   1.883 -   andalso ThmC.string_of_thm thm = 
   1.884 -           (string_of_thm (Thm.make_thm @{theory "Isac_Knowledge"}
   1.885 -               (Trueprop $ (Thm.term_of o the o (TermC.parse thy)) "9 = 3 \<up> 2"))) then ()
   1.886 -else error "rational.sml next_rule (9 - x \<up> 2) / (9 - 6 * x + x \<up> 2)";
   1.887 -\---------------------------------------------------------------------------------------/*)
   1.888 -
   1.889 -(** check, if the rule 'r' applied by the user to 't' belongs to the ruleset;
   1.890 -  if the rule is OK, the term resulting from applying the rule is returned,too;
   1.891 -  there might be several rule applications inbetween,
   1.892 -  which are listed after the head in reverse order **)
   1.893 -(*/-------------------------------------------- Isabelle2013: this gives "error id_of_thm";
   1.894 -  we don't repair this, because interaction within "reverse rewriting" never worked properly:
   1.895 -
   1.896 -  val (r, (t, asm))::_ = loc revsets t r;
   1.897 -if UnparseC.term t = "(9 - x \<up> 2) / (3 \<up> 2 + 6 * x + x \<up> 2)" andalso asm = []
   1.898 -then () else error "rational.sml locate_rule (9 - x \<up> 2) / (9 - 6 * x + x \<up> 2)";
   1.899 -
   1.900 -(* find the next rule to apply *)
   1.901 -  val SOME (r as (Thm (str, thm))) = nex revsets t;
   1.902 -if str = "sym_#power_Float ((3,0), (0,0)) __ ((2,0), (0,0))" andalso
   1.903 -   ThmC.string_of_thm thm = (string_of_thm (ThmC_Def.make_thm @{theory "Isac_Knowledge"}
   1.904 -                (Trueprop $ (Thm.term_of o the o (TermC.parse thy)) "9 = 3 \<up> 2"))) then ()
   1.905 -else error "rational.sml next_rule (9 - x \<up> 2) / (9 - 6 * x + x \<up> 2)";
   1.906 -
   1.907 -(*check the next rule*)
   1.908 -  val (r, (t, asm)) :: _ = loc revsets t r;
   1.909 -if UnparseC.term t = "(3 \<up> 2 - x \<up> 2) / (3 \<up> 2 + 6 * x + x \<up> 2)" then ()
   1.910 -else error "rational.sml locate_rule (9 - x \<up> 2) / (9 - 6 * x + x \<up> 2) II";
   1.911 -
   1.912 -(*find and check the next rules, rewrite*)
   1.913 -  val SOME r = nex revsets t;
   1.914 -  val (r,(t,asm))::_ = loc revsets t r;
   1.915 -if UnparseC.term t = "(3 \<up> 2 - x \<up> 2) / (3 \<up> 2 + 2 * 3 * x + x \<up> 2)" then ()
   1.916 -else error "rational.sml locate_rule II";
   1.917 -
   1.918 -  val SOME r = nex revsets t;
   1.919 -  val (r,(t,asm))::_ = loc revsets t r;
   1.920 -if UnparseC.term t = "(3 - x) * (3 + x) / (3 \<up> 2 + 2 * 3 * x + x \<up> 2)" then ()
   1.921 -else error "rational.sml next_rule II";
   1.922 -
   1.923 -  val SOME r = nex revsets t;
   1.924 -  val (r,(t,asm))::_ = loc revsets t r;
   1.925 -if UnparseC.term t = "(3 - x) * (3 + x) / ((3 + x) * (3 + x))" then ()
   1.926 -else error "rational.sml next_rule III";
   1.927 -
   1.928 -  val SOME r = nex revsets t;
   1.929 -  val (r, (t, asm)) :: _ = loc revsets t r;
   1.930 -  val ss = UnparseC.term t;
   1.931 -if ss = "(3 - x) / (3 + x)" andalso UnparseC.terms asm = "[\"3 + x ~= 0\"]" then ()
   1.932 -else error "rational.sml: new behav. in rev-set cancel";
   1.933 -\--------------------------------------------------------------------------------------/*)
   1.934 -
   1.935 -"-------- 'reverse-ruleset' cancel_p -----------------------------------------";
   1.936 -"-------- 'reverse-ruleset' cancel_p -----------------------------------------";
   1.937 -"-------- 'reverse-ruleset' cancel_p -----------------------------------------";
   1.938 -(*WN130909: the example below shows, why "reverse rewriting" only worked for
   1.939 -  special cases.*)
   1.940 -
   1.941 -(*the term for which reverse rewriting is demonstrated*)
   1.942 -val t = TermC.str2term "(9 + (-1)*x \<up> 2) / (9 + ((-6)*x + x \<up> 2))";
   1.943 -val Rrls {scr=Rfuns {init_state=ini,locate_rule=loc,
   1.944 -		       next_rule=nex,normal_form=nor,...},...} = cancel_p;
   1.945 -
   1.946 -(*normal_form produces the result in ONE step*)
   1.947 -val SOME (t', _) = nor t; 
   1.948 -if UnparseC.term t' = "(3 + x) / (3 + - 1 * x)"
   1.949 -then () else error "cancel_p normal_form CHANGED";;
   1.950 -
   1.951 -(*initialize the interpreter state used by the 'me'*)
   1.952 -val SOME (t', asm) = cancel_p_ thy t;
   1.953 -if (UnparseC.term t', UnparseC.terms asm) = ("(3 + x) / (3 + - 1 * x)", "[\"3 + - 1 * x \<noteq> 0\"]")
   1.954 -then () else error "cancel_p  CHANGED";;
   1.955 -
   1.956 -val (t,_,revsets,_) = ini t;
   1.957 -
   1.958 -(* WN.10.10.02: dieser Fall terminiert nicht 
   1.959 -           (make_polynomial enth"alt zu viele rules)
   1.960 -WN060823 'init_state' requires rewriting on specified location in the term
   1.961 -default_print_depth 99; Rfuns; default_print_depth 3;
   1.962 -WN060831 cycling "sym_order_mult_rls_" "sym_mult.assoc"
   1.963 -         as was with make_polynomial before ?!?* )
   1.964 -
   1.965 -val SOME r = nex revsets t;
   1.966 -eq_Thm (r, Thm ("sym_#power_Float ((3,0), (0,0)) __ ((2,0), (0,0))", 
   1.967 -		mk_thm thy "9 = 3 \<up> 2"));
   1.968 -( *WN060831 *** id_of_thm
   1.969 -           Exception- ERROR raised ...
   1.970 -val (r,(t,asm))::_ = loc revsets t r;
   1.971 -UnparseC.term t;
   1.972 -
   1.973 -  val SOME r = nex revsets t;
   1.974 -  val (r,(t,asm))::_ = loc revsets t r;
   1.975 -  UnparseC.term t;
   1.976 -*)                    
   1.977 -
   1.978 -"-------- examples: rls norm_Rational ----------------------------------------";
   1.979 -"-------- examples: rls norm_Rational ----------------------------------------";
   1.980 -"-------- examples: rls norm_Rational ----------------------------------------";
   1.981 -val t = TermC.str2term "(3*x+5)/18 - x/2  - -(3*x - 2)/9 = 0";
   1.982 -val SOME (t', _) = rewrite_set_ thy false norm_Rational t; UnparseC.term t';
   1.983 -if UnparseC.term t' = "1 / 18 = 0" then () else error "rational.sml 1";
   1.984 -
   1.985 -val t = TermC.str2term "(17*x - 51)/9 - (-(13*x - 3)/6) + 11 - (9*x - 7)/4 = 0";
   1.986 -val SOME (t',_) = rewrite_set_ thy false norm_Rational t; UnparseC.term t';
   1.987 -if UnparseC.term t' = "(237 + 65 * x) / 36 = 0" then () 
   1.988 -else error "rational.sml 2";
   1.989 -
   1.990 -val t = TermC.str2term "(1/2 + (5*x)/2) \<up> 2 - ((13*x)/2 - 5/2) \<up> 2 - (6*x) \<up> 2 + 29";
   1.991 -val SOME (t',_) = rewrite_set_ thy false norm_Rational t; UnparseC.term t';
   1.992 -if UnparseC.term t' = "23 + 35 * x + - 72 * x \<up> 2" then ()
   1.993 -else error "rational.sml 3";
   1.994 -
   1.995 -(*Rewrite.trace_on:=true;*)
   1.996 -val t = TermC.str2term "Not (6*x is_atom)";
   1.997 -val SOME (t',_) = rewrite_set_ thy false powers_erls t; UnparseC.term t';
   1.998 -"HOL.True";
   1.999 -val t = TermC.str2term "1 < 2";
  1.1000 -val SOME (t',_) = rewrite_set_ thy false powers_erls t; UnparseC.term t';
  1.1001 -"HOL.True";
  1.1002 -
  1.1003 -val t = TermC.str2term "(6*x) \<up> 2";
  1.1004 -val SOME (t',_) = rewrite_ thy dummy_ord powers_erls false 
  1.1005 -			   (ThmC.numerals_to_Free @{thm realpow_def_atom}) t;
  1.1006 -if UnparseC.term t' = "6 * x * (6 * x) \<up> (2 + - 1)" then ()
  1.1007 -else error "rational.sml powers_erls (6*x) \<up> 2";
  1.1008 -
  1.1009 -val t = TermC.str2term "-1 * (-2 * (5 / 2 * (13 * x / 2)))";
  1.1010 -val SOME (t',_) = rewrite_set_ thy false norm_Rational t; UnparseC.term t';
  1.1011 -if UnparseC.term t' = "65 * x / 2" then () else error "rational.sml 4";
  1.1012 -
  1.1013 -val t = TermC.str2term "1 - ((13*x)/2 - 5/2) \<up> 2";
  1.1014 -val SOME (t',_) = rewrite_set_ thy false norm_Rational t; UnparseC.term t';
  1.1015 -if UnparseC.term t' = "(- 21 + 130 * x + - 169 * x \<up> 2) / 4" then () 
  1.1016 -else error "rational.sml 5";
  1.1017 -
  1.1018 -(*SRAM Schalk I, p.92 Nr. 609a*)
  1.1019 -val t = TermC.str2term "2*(3 - x/5)/3 - 4*(1 - x/3) - x/3 - 2*(x/2 - 1/4)/27 +5/54";
  1.1020 -val SOME (t',_) = rewrite_set_ thy false norm_Rational t; UnparseC.term t';
  1.1021 -if UnparseC.term t' = "(- 255 + 112 * x) / 135" then () 
  1.1022 -else error "rational.sml 6";
  1.1023 -
  1.1024 -(*SRAM Schalk I, p.92 Nr. 610c*)
  1.1025 -val t = TermC.str2term "((x- 1)/(x+1) + 1) / ((x- 1)/(x+1) - (x+1)/(x- 1)) - 2";
  1.1026 -val SOME (t',_) = rewrite_set_ thy false norm_Rational t; UnparseC.term t';
  1.1027 -if UnparseC.term t' = "(3 + x) / - 2" then () else error "rational.sml 7";
  1.1028 -
  1.1029 -(*SRAM Schalk I, p.92 Nr. 476a*)
  1.1030 -val t = TermC.str2term "(x \<up> 2/(1 - x \<up> 2) + 1)/(x/(1 - x) + 1) * (1 + x)";
  1.1031 -(*. a/b : c/d translated to a/b * d/c .*)
  1.1032 -val SOME (t',_) = rewrite_set_ thy false norm_Rational t; UnparseC.term t';
  1.1033 -if UnparseC.term t' = "1" then () else error "rational.sml 8";
  1.1034 -
  1.1035 -(*Schalk I, p.92 Nr. 472a*)
  1.1036 -val t = TermC.str2term "((8*x \<up> 2 - 32*y \<up> 2)/(2*x + 4*y))/((4*x - 8*y)/(x + y))";
  1.1037 -val SOME (t',_) = rewrite_set_ thy false norm_Rational t; UnparseC.term t';
  1.1038 -if UnparseC.term t' = "x + y" then () else error "rational.sml p.92 Nr. 472a";
  1.1039 -
  1.1040 -(*Schalk I, p.70 Nr. 480b: SEE rational.sml --- nonterminating rls norm_Rational ---*)
  1.1041 -
  1.1042 -(*WN130910 add_fractions_p exception Div raised + history:
  1.1043 -### WN.2.6.03 from rlang.sml 56a 
  1.1044 -val t = TermC.str2term "(a + b * x) / (a + -1 * (b * x)) + (-1 * a + b * x) / (a + b * x) = 4 * (a * b) / (a \<up> 2 + -1 * b \<up> 2)";
  1.1045 -val NONE = rewrite_set_ thy false add_fractions_p t;
  1.1046 -
  1.1047 -THE ERROR ALREADY OCCURS IN THIS PART:
  1.1048 -val t = TermC.str2term "(a + b * x) / (a + -1 * (b * x)) + (-1 * a + b * x) / (a + b * x)";
  1.1049 -val NONE = add_fraction_p_ thy t;
  1.1050 -
  1.1051 -SEE Test_Some.thy: section {* add_fractions_p downto exception Div raised ===
  1.1052 -*)
  1.1053 -
  1.1054 -"-------- rational numerals --------------------------------------------------";
  1.1055 -"-------- rational numerals --------------------------------------------------";
  1.1056 -"-------- rational numerals --------------------------------------------------";
  1.1057 -(*SRA Schalk I, p.40 Nr. 164b *)
  1.1058 -val t = TermC.str2term "(47/6 - 76/9 + 13/4)/(35/12)";
  1.1059 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1060 -if UnparseC.term t = "19 / 21" then ()
  1.1061 -else error "rational.sml: diff.behav. in norm_Rational_mg 1";
  1.1062 -
  1.1063 -(*SRA Schalk I, p.40 Nr. 166a *)
  1.1064 -val t = TermC.str2term "((5/4)/(4+22/7) + 37/20)*(110/3 - 110/9 * 23/11)";
  1.1065 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1066 -if UnparseC.term t = "45 / 2" then ()
  1.1067 -else error "rational.sml: diff.behav. in norm_Rational_mg 2";
  1.1068 -
  1.1069 -"-------- examples cancellation from: Mathematik 1 Schalk --------------------";
  1.1070 -"-------- examples cancellation from: Mathematik 1 Schalk --------------------";
  1.1071 -"-------- examples cancellation from: Mathematik 1 Schalk --------------------";
  1.1072 -(* e190c Stefan K.*)
  1.1073 -val t = TermC.str2term "((1 + 9*a \<up> 2) * (1 + 3*a)) / ((3*a + 9*a \<up> 2) * (1 + 3*a))";
  1.1074 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1075 -if UnparseC.term t = "(1 + 9 * a \<up> 2) / (3 * a + 9 * a \<up> 2)"
  1.1076 -then () else error "rational.sml: diff.behav. in norm_Rational_mg 3";
  1.1077 -
  1.1078 -(* e192b Stefan K.*)
  1.1079 -val t = TermC.str2term "(x \<up> 2 * (7*x + (-1)*y))  /  (y \<up> 2 * (7*x + (-1)*y))";
  1.1080 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1081 -if UnparseC.term t = "x \<up> 2 / y \<up> 2"
  1.1082 -then () else error "rational.sml: diff.behav. in norm_Rational_mg 4";
  1.1083 -
  1.1084 -(*SRC Schalk I, p.66 Nr. 379c *)
  1.1085 -val t = TermC.str2term "(a - b)/(b - a)";
  1.1086 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1087 -if UnparseC.term t = "- 1"
  1.1088 -then () else error "rational.sml: diff.behav. in norm_Rational_mg 5";
  1.1089 -
  1.1090 -(*SRC Schalk I, p.66 Nr. 380b *)
  1.1091 -val t = TermC.str2term "15*(3*x + 3) * (4*x + 9)  /  (12*(2*x + 7) * (5*x + 5))";
  1.1092 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1093 -if UnparseC.term t = "(27 + 12 * x) / (28 + 8 * x)"
  1.1094 -then () else error "rational.sml: diff.behav. in norm_Rational_mg 6";
  1.1095 -
  1.1096 -(*Schalk I, p.60 Nr. 215c *)
  1.1097 -val t = TermC.str2term "(a + b) \<up> 4 * (x - y)  /  ((x - y) \<up> 3 * (a + b) \<up> 2)";
  1.1098 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1099 -if UnparseC.term t = "(a \<up> 2 + 2 * a * b + b \<up> 2) / (x \<up> 2 + - 2 * x * y + y \<up> 2)"
  1.1100 -then () else error "rational.sml: diff.behav. in norm_Rational_mg 7";
  1.1101 -
  1.1102 -(*SRC Schalk I, p.66 Nr. 381b *)
  1.1103 -val t = TermC.str2term 
  1.1104 -"(4*x \<up> 2 - 20*x + 25)/(2*x - 5) \<up> 3";
  1.1105 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1106 -if UnparseC.term t = "1 / (- 5 + 2 * x)"
  1.1107 -then () else error "rational.sml: diff.behav. in norm_Rational_mg 9";
  1.1108 -
  1.1109 -(* e190c Stefan K.*)
  1.1110 -val t = TermC.str2term "((1 + 9*a \<up> 2) * (1 + 3*a))  /  ((3*a + 9*a \<up> 2) * (1 + 3 * a))";
  1.1111 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1112 -if UnparseC.term t =  "(1 + 9 * a \<up> 2) / (3 * a + 9 * a \<up> 2)"
  1.1113 -then () else error "rational.sml: diff.behav. in norm_Rational_mg 3";
  1.1114 -
  1.1115 -(* e192b Stefan K.*)
  1.1116 -val t = TermC.str2term "(x \<up> 2 * (7*x + (-1)*y))  /  (y \<up> 2 * (7*x + (-1)*y))";
  1.1117 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1118 -if UnparseC.term t = "x \<up> 2 / y \<up> 2"
  1.1119 -then () else error "rational.sml: diff.behav. in norm_Rational_mg 4";
  1.1120 -
  1.1121 -(*SRC Schalk I, p.66 Nr. 379c *)
  1.1122 -val t = TermC.str2term "(a - b) / (b - a)";
  1.1123 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1124 -if UnparseC.term t = "- 1"
  1.1125 -then () else error "rational.sml: diff.behav. in norm_Rational_mg 5";
  1.1126 -
  1.1127 -(*SRC Schalk I, p.66 Nr. 380b *)
  1.1128 -val t = TermC.str2term "15*(3*x + 3) * (4*x + 9)  /  (12*(2*x + 7) * (5*x + 5))";
  1.1129 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1130 -if UnparseC.term t = "(27 + 12 * x) / (28 + 8 * x)"
  1.1131 -then () else error "rational.sml: diff.behav. in norm_Rational_mg 6";
  1.1132 -
  1.1133 -(*Schalk I, p.60 Nr. 215c *)
  1.1134 -val t = TermC.str2term "(a + b) \<up> 4 * (x - y)  /  ((x - y) \<up> 3 * (a + b) \<up> 2)";
  1.1135 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1136 -if UnparseC.term t = "(a \<up> 2 + 2 * a * b + b \<up> 2) / (x \<up> 2 + - 2 * x * y + y \<up> 2)"
  1.1137 -then () else error "Schalk I, p.60 Nr. 215c: with Isabelle2002 cancellation incomplete, changed";
  1.1138 -
  1.1139 -(* extreme example from somewhere *)
  1.1140 -val t = TermC.str2term 
  1.1141 -    ("(a \<up> 4 * x  +  -1*a \<up> 4 * y  +  4*a \<up> 3 * b * x  +  -4*a \<up> 3 * b * y  + " ^
  1.1142 -      "6*a \<up> 2 * b \<up> 2 * x  +  -6*a \<up> 2 * b \<up> 2 * y  +  4*a * b \<up> 3 * x  +  -4*a * b \<up> 3 * y  + " ^
  1.1143 -      "b \<up> 4 * x  +  -1*b \<up> 4 * y) " ^
  1.1144 -  " / (a \<up> 2 * x \<up> 3  +  -3*a \<up> 2 * x \<up> 2 * y  +  3*a \<up> 2 * x * y \<up> 2  +  -1*a \<up> 2 * y \<up> 3 + " ^
  1.1145 -      "2*a * b * x \<up> 3  +  -6*a * b * x \<up> 2 * y  +  6*a * b * x * y \<up> 2  +  -2*a * b * y \<up> 3 + " ^
  1.1146 -      "b \<up> 2 * x \<up> 3  +  -3*b \<up> 2 * x \<up> 2 * y  +  3*b \<up> 2 * x * y \<up> 2  +  -1*b \<up> 2 * y \<up> 3)")
  1.1147 -val SOME (t, _) = rewrite_set_ thy false cancel_p t;
  1.1148 -if UnparseC.term t = "(a \<up> 2 + 2 * a * b + b \<up> 2) / (x \<up> 2 + - 2 * x * y + y \<up> 2)"
  1.1149 -then () else error "with Isabelle2002: NONE -- now SOME changed";
  1.1150 -
  1.1151 -(*Schalk I, p.66 Nr. 381a *)
  1.1152 -(* ATTENTION: here the rls is very slow. In Isabelle2002 this required 2 min *)
  1.1153 -val t = TermC.str2term "18*(a + b) \<up> 3 * (a - b) \<up> 2 / (72*(a - b) \<up> 3 * (a + b) \<up> 2)";
  1.1154 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1155 -if UnparseC.term t = "(a + b) / (4 * a + - 4 * b)"
  1.1156 -then () else error "rational.sml: diff.behav. in norm_Rational_mg 8";
  1.1157 -
  1.1158 -(*SRC Schalk I, p.66 Nr. 381b *)
  1.1159 -val t = TermC.str2term "(4*x \<up> 2 - 20*x + 25) / (2*x - 5) \<up> 3";
  1.1160 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1161 -if UnparseC.term t = "1 / (- 5 + 2 * x)"
  1.1162 -then () else error "rational.sml: diff.behav. in norm_Rational_mg 9";
  1.1163 -
  1.1164 -(*SRC Schalk I, p.66 Nr. 381c *)
  1.1165 -val t = TermC.str2term "(27*a \<up> 3 + 9*a \<up> 2+3*a+1) / (27*a \<up> 3 + 18*a \<up> 2+3*a)";
  1.1166 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1167 -if UnparseC.term t = "(1 + 9 * a \<up> 2) / (3 * a + 9 * a \<up> 2)"
  1.1168 -then () else error "rational.sml: diff.behav. in norm_Rational_mg 10";
  1.1169 -
  1.1170 -(*SRC Schalk I, p.66 Nr. 383a *)
  1.1171 -val t = TermC.str2term "(5*a \<up> 2 - 5*a*b) / (a - b) \<up> 2";
  1.1172 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1173 -if UnparseC.term t = "- 5 * a / (- 1 * a + b)"
  1.1174 -then () else error "rational.sml: diff.behav. in norm_Rational_mg 11";
  1.1175 -
  1.1176 -"----- NOT TERMINATING ?: worked before 0707xx";
  1.1177 -val t = TermC.str2term "(a \<up> 2 - 1)*(b + 1) / ((b \<up> 2 - 1)*(a+1))";
  1.1178 -(* WN130911 "exception Div raised" by 
  1.1179 -  cancel_p_ thy (TermC.str2term ("(-1 + -1 * b + a \<up> 2 + a \<up> 2 * b) /" ^
  1.1180 -                           "(-1 + -1 * a + b \<up> 2 + a * b \<up> 2)"))
  1.1181 -
  1.1182 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1183 -if UnparseC.term t = "(1 + -1 * a) / (1 + -1 * b)" then ()
  1.1184 -else error "rational.sml MG tests 3e";
  1.1185 -*)
  1.1186 -
  1.1187 -"-------- examples common denominator from: Mathematik 1 Schalk --------------";
  1.1188 -"-------- examples common denominator from: Mathematik 1 Schalk --------------";
  1.1189 -"-------- examples common denominator from: Mathematik 1 Schalk --------------";
  1.1190 -(*SRA Schalk I, p.67 Nr. 403a *)
  1.1191 -val t = TermC.str2term "4/x - 3/y - 1";
  1.1192 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1193 -if UnparseC.term t = "(- 3 * x + 4 * y + - 1 * x * y) / (x * y)"
  1.1194 -then () else error "rational.sml: diff.behav. in norm_Rational_mg 12";
  1.1195 -
  1.1196 -val t = TermC.str2term "(2*a+3*b)/(b*c) + (3*c+a)/(a*c) - (2*a \<up> 2+3*b*c)/(a*b*c)";
  1.1197 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1198 -if UnparseC.term t = "4 / c"
  1.1199 -then () else error "rational.sml: diff.behav. in norm_Rational_mg 13";
  1.1200 -
  1.1201 -(*SRA Schalk I, p.67 Nr. 410b *)
  1.1202 -val t = TermC.str2term "1/(x+1) + 1/(x+2) - 2/(x+3)";
  1.1203 -(* WN130911 non-termination due to non-termination of
  1.1204 -  cancel_p_ thy (TermC.str2term "(5 + 3 * x) / (6 + 11 * x + 6 * x \<up> 2 + x \<up> 3)")
  1.1205 -
  1.1206 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1207 -if UnparseC.term t = "(5 + 3 * x) / (6 + 11 * x + 6 * x \<up> 2 + x \<up> 3)"
  1.1208 -then () else error "rational.sml: diff.behav. in norm_Rational_mg 14";
  1.1209 -*)
  1.1210 -
  1.1211 -(*SRA Schalk I, p.67 Nr. 413b *)
  1.1212 -val t = TermC.str2term "(1 + x)/(1 - x)  -  (1 - x)/(1 + x)  +  2*x/(1 - x \<up> 2)";
  1.1213 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1214 -if UnparseC.term t = "6 * x / (1 + - 1 * x \<up> 2)"
  1.1215 -then () else error "rational.sml: diff.behav. in norm_Rational_mg 15";
  1.1216 -
  1.1217 -(*SRA Schalk I, p.68 Nr. 414a *)
  1.1218 -val t = TermC.str2term "(x + 2)/(x - 1)  +  (x - 3)/(x - 2)  -  (x + 1)/((x - 1)*(x - 2))";
  1.1219 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1220 -if UnparseC.term t ="(- 2 + - 5 * x + 2 * x \<up> 2) / (2 + - 3 * x + x \<up> 2)"
  1.1221 -then () else error "rational.sml: diff.behav. in norm_Rational_mg 16";
  1.1222 -
  1.1223 -(*SRA Schalk I, p.68 Nr. 428b *)
  1.1224 -val t = TermC.str2term 
  1.1225 -  "1/(a - b) \<up> 2  +  1/(a + b) \<up> 2  -  2/(a \<up> 2 - b \<up> 2)  -  4*(b \<up> 2 - 1)/(a \<up> 2 - b \<up> 2) \<up> 2";
  1.1226 -(* WN130911 non-termination due to non-termination of
  1.1227 -  cancel_p_ thy (TermC.str2term "(4 + -4 * b \<up> 2) / (a \<up> 4 + -2 * (a \<up> 2 * b \<up> 2) + b \<up> 4)")
  1.1228 -
  1.1229 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1230 -if UnparseC.term t = "4 / (a \<up> 4 + -2 * a \<up> 2 * b \<up> 2 + b \<up> 4)"
  1.1231 -then () else error "rational.sml: diff.behav. in norm_Rational_mg 18";
  1.1232 -*)
  1.1233 -
  1.1234 -(*SRA Schalk I, p.68 Nr. 430b *)
  1.1235 -val t = TermC.str2term 
  1.1236 -  "a \<up> 2/(a - 3*b) - 108*a*b \<up> 3/((a+3*b)*(a \<up> 2 - 9*b \<up> 2)) - 9*b \<up> 2*(a - 3*b)/(a+3*b) \<up> 2";
  1.1237 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1238 -if UnparseC.term t = "a + 3 * b"
  1.1239 -then () else error "rational.sml: diff.behav. in norm_Rational_mg 19";
  1.1240 -
  1.1241 -(*SRA Schalk I, p.68 Nr. 432 *)
  1.1242 -val t = TermC.str2term 
  1.1243 -  ("(a \<up> 2 + a*b) / (a \<up> 2 - b \<up> 2)  -  (b \<up> 2 - a*b) / (b \<up> 2 - a \<up> 2)  +  " ^
  1.1244 -  "a \<up> 2*(a - b) / (a \<up> 3 - a \<up> 2*b)  -  2*a*(a \<up> 2 - b \<up> 2) / (a \<up> 3 - a*b \<up> 2)  -  " ^
  1.1245 -  "2*b \<up> 2 / (a \<up> 2 - b \<up> 2)");
  1.1246 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1247 -if UnparseC.term t = (*"0" ..isabisac15 | Isabelle2017..*)  "0 / (a \<up> 2 + - 1 * b \<up> 2)"
  1.1248 -then () else error "rational.sml: diff.behav. in norm_Rational_mg 20";
  1.1249 -
  1.1250 -(* some example *)
  1.1251 -val t = TermC.str2term "3*a / (a*b)  +  x/y";
  1.1252 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1253 -if UnparseC.term t = "(3 * y + b * x) / (b * y)"
  1.1254 -then () else error "rational.sml: diff.behav. in norm_Rational_mg 21";
  1.1255 -
  1.1256 -
  1.1257 -"-------- examples multiply and cancel from: Mathematik 1 Schalk -------------";
  1.1258 -"-------- examples multiply and cancel from: Mathematik 1 Schalk -------------";
  1.1259 -"-------- examples multiply and cancel from: Mathematik 1 Schalk -------------";
  1.1260 -(*------- SRM Schalk I, p.68 Nr. 436a *)
  1.1261 -val t = TermC.str2term "3*(x+y) / (15*(x - y))  *   25*(x - y) \<up> 2 / (18*(x + y) \<up> 2)";
  1.1262 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1263 -if UnparseC.term t = "(- 5 * x + 5 * y) / (- 18 * x + - 18 * y)"
  1.1264 -then () else error "rational.sml: diff.behav. in norm_Rational_mg 22";
  1.1265 -
  1.1266 -(*------- SRM.test Schalk I, p.68 Nr. 436b *)
  1.1267 -val t = TermC.str2term "5*a*(a - b) \<up> 2*(a + b) \<up> 3/(7*b*(a - b) \<up> 3) * 7*b/(a + b) \<up> 3";
  1.1268 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1269 -if UnparseC.term t = "5 * a / (a + - 1 * b)"
  1.1270 -then () else error "rational.sml: diff.behav. in norm_Rational_mg 23";
  1.1271 -
  1.1272 -(*------- Schalk I, p.68 Nr. 437a *)
  1.1273 -val t = TermC.str2term "(3*a - 4*b) / (4*c+3*e)  *  (3*a+4*b)/(9*a \<up> 2 - 16*b \<up> 2)";
  1.1274 -(* raises an exception for unclear reasons:
  1.1275 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1276 -:
  1.1277 -###  rls: cancel_p on: (9 * a \<up> 2 + -16 * b \<up> 2) / (4 * c + 3 * e) /
  1.1278 -(9 * a \<up> 2 + -16 * b \<up> 2) 
  1.1279 -exception Div raised
  1.1280 -
  1.1281 -BUT
  1.1282 -val t = TermC.str2term 
  1.1283 -  ("(9 * a \<up> 2 + -16 * b \<up> 2) / (4 * c + 3 * e) /" ^
  1.1284 -  "(9 * a \<up> 2 + -16 * b \<up> 2)");
  1.1285 -NONE = cancel_p_ thy t;
  1.1286 -
  1.1287 -if UnparseC.term t = "1 / (4 * c + 3 * e)" then ()
  1.1288 -else error "rational.sml: diff.behav. in norm_Rational_mg 24";
  1.1289 -*)
  1.1290 -
  1.1291 -"----- S.K. corrected non-termination 060904";
  1.1292 -val t = TermC.str2term "(3*a - 4*b) * (3*a+4*b)/((4*c+3*e)*(9*a \<up> 2 - 16*b \<up> 2))";
  1.1293 -val SOME (t, _) = rewrite_set_ thy false make_polynomial t;
  1.1294 -if UnparseC.term t = 
  1.1295 -  "(9 * a \<up> 2 + - 16 * b \<up> 2) /\n(36 * a \<up> 2 * c + 27 * a \<up> 2 * e + - 64 * b \<up> 2 * c +\n - 48 * b \<up> 2 * e)"
  1.1296 -then () else error "rational.sml: S.K.8..corrected 060904-6";
  1.1297 -
  1.1298 -"----- S.K. corrected non-termination of cancel_p_";
  1.1299 -val t'' = TermC.str2term ("(9 * a \<up> 2 + -16 * b \<up> 2) /" ^
  1.1300 -  "(36 * a \<up> 2 * c + (27 * a \<up> 2 * e + (-64 * b \<up> 2 * c + -48 * b \<up> 2 * e)))");
  1.1301 -(* /--- DOES NOT TERMINATE AT TRANSITION isabisac15 --> Isabelle2017 --------------------------\
  1.1302 -val SOME (t',_) = rewrite_set_ thy false cancel_p t'';
  1.1303 -if UnparseC.term t' = "1 / (4 * c + 3 * e)"
  1.1304 -then () else error "rational.sml: diff.behav. in cancel_p S.K.8";
  1.1305 -   \--- DOES NOT TERMINATE AT TRANSITION isabisac15 --> Isabelle2017 --------------------------/*)
  1.1306 -
  1.1307 -(*------- Schalk I, p.68 Nr. 437b*)
  1.1308 -val t = TermC.str2term "(a + b)/(x \<up> 2 - y \<up> 2) * ((x - y) \<up> 2/(a \<up> 2 - b \<up> 2))";
  1.1309 -(*val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1310 -:
  1.1311 -####  rls: cancel_p on: (a * x \<up> 2 + -2 * (a * (x * y)) + a * y \<up> 2 + b * x \<up> 2 +
  1.1312 - -2 * (b * (x * y)) +
  1.1313 - b * y \<up> 2) /
  1.1314 -(a \<up> 2 * x \<up> 2 + -1 * (a \<up> 2 * y \<up> 2) + -1 * (b \<up> 2 * x \<up> 2) +
  1.1315 - b \<up> 2 * y \<up> 2) 
  1.1316 -exception Div raised
  1.1317 -*)
  1.1318 -
  1.1319 -(*------- SRM Schalk I, p.68 Nr. 438a *)
  1.1320 -val t = TermC.str2term "x*y / (x*y - y \<up> 2)  *  (x \<up> 2 - x*y)";
  1.1321 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1322 -if UnparseC.term t = "x \<up> 2"
  1.1323 -then () else error "rational.sml: diff.behav. in norm_Rational_mg 24";
  1.1324 -
  1.1325 -(*------- SRM Schalk I, p.68 Nr. 439b *)
  1.1326 -val t = TermC.str2term "(4*x \<up> 2 + 4*x + 1)  *  ((x \<up> 2 - 2*x \<up> 3) / (4*x \<up> 2 + 2*x))";
  1.1327 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1328 -if UnparseC.term t = "(x + - 4 * x \<up> 3) / 2"
  1.1329 -then () else error "rational.sml: diff.behav. in norm_Rational_mg 25";
  1.1330 -
  1.1331 -(*------- SRM Schalk I, p.68 Nr. 440a *)
  1.1332 -val t = TermC.str2term "(x \<up> 2 - 2*x) / (x \<up> 2 - 3*x)  *  (x - 3) \<up> 2 / (x \<up> 2 - 4)";
  1.1333 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1334 -if UnparseC.term t = "(- 3 + x) / (2 + x)"
  1.1335 -then () else error "rational.sml: diff.behav. in norm_Rational_mg 26";
  1.1336 -
  1.1337 -"----- Schalk I, p.68 Nr. 440b SK11 works since 0707xx";
  1.1338 -val t = TermC.str2term "(a \<up> 3 - 9*a) / (a \<up> 3*b - a*b \<up> 3)  *  (a \<up> 2*b + a*b \<up> 2) / (a+3)";
  1.1339 -(* WN130911 non-termination for unclear reasons:
  1.1340 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1341 -
  1.1342 -... ENDS WITH THIS TRACE:
  1.1343 -:
  1.1344 -###  rls: cancel_p on: (-9 * (a \<up> 3 * b) + -9 * (a \<up> 2 * b \<up> 2) + a \<up> 5 * b +
  1.1345 - a \<up> 4 * b \<up> 2) /
  1.1346 -(a \<up> 3 * b + -1 * (a * b \<up> 3)) /
  1.1347 -(3 + a)
  1.1348 -BUT THIS IS CORRECTLY RECOGNISED 
  1.1349 -val t = TermC.str2term 
  1.1350 -  ("(-9 * (a \<up> 3 * b) + -9 * (a \<up> 2 * b \<up> 2) + a \<up> 5 * b + a \<up> 4 * b \<up> 2)  /" ^
  1.1351 -  "(a \<up> 3 * b + -1 * (a * b \<up> 3))  /  (3 + (a::real))");
  1.1352 -AS
  1.1353 -NONE = cancel_p_ thy t;
  1.1354 -
  1.1355 -if UnparseC.term t = "(-3 * a + a \<up> 2) / (a + -1 * b)" then ()
  1.1356 -else error "rational.sml: diff.behav. in norm_Rational 27";
  1.1357 -*)
  1.1358 -
  1.1359 -"----- SK12 works since 0707xx";
  1.1360 -val t = TermC.str2term "(a \<up> 3 - 9*a) * (a \<up> 2*b+a*b \<up> 2)  /  ((a \<up> 3*b - a*b \<up> 3) * (a+3))";
  1.1361 -(* WN130911 non-termination due to non-termination of
  1.1362 -  cancel_p_ thy (TermC.str2term "(4 + -4 * b \<up> 2) / (a \<up> 4 + -2 * (a \<up> 2 * b \<up> 2) + b \<up> 4)")
  1.1363 -
  1.1364 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1365 -if UnparseC.term t' = "(-3 * a + a \<up> 2) / (a + -1 * b)" then ()
  1.1366 -else error "rational.sml: diff.behav. in norm_Rational 28";
  1.1367 -*)
  1.1368 -
  1.1369 -"-------- examples common denominator and multiplication from: Schalk --------";
  1.1370 -"-------- examples common denominator and multiplication from: Schalk --------";
  1.1371 -"-------- examples common denominator and multiplication from: Schalk --------";
  1.1372 -(*------- SRAM Schalk I, p.69 Nr. 441b *)
  1.1373 -val t = TermC.str2term "(4*a/3 + 3*b \<up> 2/a \<up> 3 + b/(4*a))*(4*b/(3*a))";
  1.1374 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1375 -if UnparseC.term t = "(36 * b \<up> 3 + 3 * a \<up> 2 * b \<up> 2 + 16 * a \<up> 4 * b) /\n(9 * a \<up> 4)"
  1.1376 -then () else error "rational.sml: diff.behav. in norm_Rational_mg 28";
  1.1377 -
  1.1378 -(*------- SRAM Schalk I, p.69 Nr. 442b *)
  1.1379 -val t = TermC.str2term ("(15*a \<up> 2/x \<up> 3 - 5*b \<up> 4/x \<up> 2 + 25*c \<up> 2/x) * " ^
  1.1380 -  "(x \<up> 3/(5*a*b \<up> 3*c \<up> 3)) + 1/c \<up> 3 * (b*x/a - 3*a/b \<up> 3)");
  1.1381 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1382 -if UnparseC.term t = "5 * x \<up> 2 / (a * b \<up> 3 * c)"
  1.1383 -then () else error "rational.sml: diff.behav. in norm_Rational_mg 29";
  1.1384 -
  1.1385 -(*------- SRAM Schalk I, p.69 Nr. 443b *)
  1.1386 -val t = TermC.str2term "(a/2 + b/3) * (b/3 - a/2)";
  1.1387 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1388 -if UnparseC.term t = "(- 9 * a \<up> 2 + 4 * b \<up> 2) / 36"
  1.1389 -then () else error "rational.sml: diff.behav. in norm_Rational_mg 30";
  1.1390 -
  1.1391 -(*------- SRAM Schalk I, p.69 Nr. 445b *)
  1.1392 -val t = TermC.str2term "(a \<up> 2/9 + 2*a/(3*b) + 4/b \<up> 2)*(a/3 - 2/b) + 8/b \<up> 3";
  1.1393 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1394 -if UnparseC.term t = "a \<up> 3 / 27"
  1.1395 -then () else error "rational.sml: diff.behav. in norm_Rational_mg 31";
  1.1396 -
  1.1397 -(*------- SRAM Schalk I, p.69 Nr. 446b *)
  1.1398 -val t = TermC.str2term "(x/(5*x + 4*y) - y/(5*x - 4*y) + 1)*(25*x \<up> 2 - 16*y \<up> 2)";
  1.1399 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1400 -if UnparseC.term t = (*"30 * x \<up> 2 + -9 * x * y + -20 * y \<up> 2" ..isabisac15 | Isabelle2017..*)
  1.1401 -                  "(- 30 * x \<up> 2 + 9 * x * y + 20 * y \<up> 2) / - 1"
  1.1402 -then () else error "rational.sml: diff.behav. in norm_Rational_mg 32";
  1.1403 -
  1.1404 -(*------- SRAM Schalk I, p.69 Nr. 449a *)(*Achtung: rechnet ca 8 Sekunden*)
  1.1405 -val t = TermC.str2term 
  1.1406 -"(2*x \<up> 2/(3*y)+x/y \<up> 2)*(4*x \<up> 4/(9*y \<up> 2)+x \<up> 2/y \<up> 4)*(2*x \<up> 2/(3*y) - x/y \<up> 2)";
  1.1407 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1408 -if UnparseC.term t = "(- 81 * x \<up> 4 + 16 * x \<up> 8 * y \<up> 4) / (81 * y \<up> 8)"
  1.1409 -then () else error "rational.sml: diff.behav. in norm_Rational_mg 33";
  1.1410 -
  1.1411 -(*------- SRAM Schalk I, p.69 Nr. 450a *)
  1.1412 -val t = TermC.str2term 
  1.1413 -"(4*x/(3*y)+2*y/(3*x)) \<up> 2 - (2*y/(3*x) - 2*x/y)*(2*y/(3*x)+2*x/y)";
  1.1414 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1415 -if UnparseC.term t = "(52 * x \<up> 2 + 16 * y \<up> 2) / (9 * y \<up> 2)"
  1.1416 -then () else error "rational.sml: diff.behav. in norm_Rational_mg 34";
  1.1417 -
  1.1418 -(*------- SRAM Schalk I, p.69 Nr. 442b --- abgewandelt*)
  1.1419 -val t = TermC.str2term 
  1.1420 -  ("(15*a \<up> 4/(a*x \<up> 3)  -  5*a*((b \<up> 4 - 5*c \<up> 2*x) / x \<up> 2))  *  " ^
  1.1421 -  "(x \<up> 3/(5*a*b \<up> 3*c \<up> 3))   +   a/c \<up> 3 * (x*(b/a) - 3*b*(a/b \<up> 4))");
  1.1422 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1423 -if UnparseC.term t = "5 * x \<up> 2 / (b \<up> 3 * c)"
  1.1424 -then () else error "rational.sml: diff.behav. in norm_Rational_mg 53";
  1.1425 -
  1.1426 -
  1.1427 -"-------- examples double fractions from: Mathematik 1 Schalk ----------------";
  1.1428 -"-------- examples double fractions from: Mathematik 1 Schalk ----------------";
  1.1429 -"-------- examples double fractions from: Mathematik 1 Schalk ----------------";
  1.1430 -"----- SRD Schalk I, p.69 Nr. 454b";
  1.1431 -val t = TermC.str2term "((2 - x)/(2*a)) / (2*a/(x - 2))";
  1.1432 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1433 -if UnparseC.term t = "(- 4 + 4 * x + - 1 * x \<up> 2) / (4 * a \<up> 2)"
  1.1434 -then () else error "rational.sml: diff.behav. in norm_Rational_mg 35";
  1.1435 -
  1.1436 -"----- SRD Schalk I, p.69 Nr. 455a";
  1.1437 -val t = TermC.str2term "(a \<up> 2 + 1)/(a \<up> 2 - 1) / ((a+1)/(a - 1))";
  1.1438 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1439 -if UnparseC.term t = "(1 + a \<up> 2) / (1 + 2 * a + a \<up> 2)" then ()
  1.1440 -else error "rational.sml: diff.behav. in norm_Rational_mg 36";
  1.1441 -
  1.1442 -"----- Schalk I, p.69 Nr. 455b";
  1.1443 -val t = TermC.str2term "(x \<up> 2 - 4)/(y \<up> 2 - 9)/((2+x)/(3 - y))";
  1.1444 -(* WN130911 non-termination due to non-termination of
  1.1445 -  cancel_p_ thy (TermC.str2term ("(-12 + 4 * y + 3 * x \<up> 2 + -1 * (x \<up> 2 * y)) /" ^
  1.1446 -                           "(-18 + -9 * x + 2 * y \<up> 2 + x * y \<up> 2)"))
  1.1447 -
  1.1448 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1449 -if UnparseC.term t = "(2 + -1 * x) / (3 + y)" then ()
  1.1450 -else error "rational.sml: diff.behav. in norm_Rational_mg 37";
  1.1451 -*)
  1.1452 -
  1.1453 -"----- SK060904-1a non-termination of cancel_p_ ?: worked before 0707xx";
  1.1454 -val t = TermC.str2term "(x \<up> 2 - 4)*(3 - y) / ((y \<up> 2 - 9)*(2+x))";
  1.1455 -(* WN130911 non-termination due to non-termination of
  1.1456 -  cancel_p_ thy (TermC.str2term ("(-12 + 4 * y + 3 * x \<up> 2 + -1 * (x \<up> 2 * y)) /" ^
  1.1457 -                           "(-18 + -9 * x + 2 * y \<up> 2 + x * y \<up> 2)"))
  1.1458 -
  1.1459 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1460 -if UnparseC.term t = "(2 + -1 * x) / (3 + y)" then ()
  1.1461 -else error "rational.sml: diff.behav. in norm_Rational_mg 37b";
  1.1462 -*)
  1.1463 -
  1.1464 -"----- ?: worked before 0707xx";
  1.1465 -val t = TermC.str2term "(3 + -1 * y) / (-9 + y \<up> 2)";
  1.1466 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1467 -if UnparseC.term t = "- 1 / (3 + y)"
  1.1468 -then () else error "rational.sml: -1 / (3 + y) norm_Rational";
  1.1469 -
  1.1470 -"----- SRD Schalk I, p.69 Nr. 456b";
  1.1471 -val t = TermC.str2term "(b \<up> 3 - b \<up> 2) / (b \<up> 2+b) / (b \<up> 2 - 1)";
  1.1472 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1473 -if UnparseC.term t = "b / (1 + 2 * b + b \<up> 2)"
  1.1474 -then () else error "rational.sml: diff.behav. in norm_Rational_mg 38";
  1.1475 -
  1.1476 -"----- SRD Schalk I, p.69 Nr. 457b";
  1.1477 -val t = TermC.str2term "(16*a \<up> 2 - 9*b \<up> 2)/(2*a+3*a*b) / ((4*a+3*b)/(4*a \<up> 2 - 9*a \<up> 2*b \<up> 2))";
  1.1478 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1479 -if UnparseC.term t = "8 * a \<up> 2 + - 6 * a * b + - 12 * a \<up> 2 * b + 9 * a * b \<up> 2"
  1.1480 -then () else error "rational.sml: diff.behav. in norm_Rational_mg 39";
  1.1481 -
  1.1482 -"----- Schalk I, p.69 Nr. 458b works since 0707";
  1.1483 -val t = TermC.str2term "(2*a \<up> 2*x - a \<up> 2) / (a*x - b*x) / (b \<up> 2*(2*x - 1) / (x*(a - b)))";
  1.1484 -(*val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1485 -:
  1.1486 -###  rls: cancel_p on: (-1 * a \<up> 2 + 2 * (a \<up> 2 * x)) / (a * x + -1 * (b * x)) /
  1.1487 -((-1 * b \<up> 2 + 2 * (b \<up> 2 * x)) / (a * x + -1 * (b * x))) 
  1.1488 -exception Div raised
  1.1489 -
  1.1490 -BUT
  1.1491 -val t = TermC.str2term 
  1.1492 -  ("(-1 * a \<up> 2 + 2 * (a \<up> 2 * x)) / (a * x + -1 * (b * x)) /" ^
  1.1493 -  "((-1 * b \<up> 2 + 2 * (b \<up> 2 * x)) / (a * x + -1 * (b * x)))");
  1.1494 -NONE = cancel_p_ thy t;
  1.1495 -
  1.1496 -if UnparseC.term t = "a \<up> 2 / b \<up> 2" then ()
  1.1497 -else error "rational.sml: diff.behav. in norm_Rational_mg 39b";
  1.1498 -*)
  1.1499 -
  1.1500 -"----- SRD Schalk I, p.69 Nr. 459b";
  1.1501 -val t = TermC.str2term "(a \<up> 2 - b \<up> 2)/(a*b) / (4*(a+b) \<up> 2/a)";
  1.1502 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1503 -if UnparseC.term t = "(a + - 1 * b) / (4 * a * b + 4 * b \<up> 2)" then ()
  1.1504 -else error "rational.sml: diff.behav. in norm_Rational_mg 41";
  1.1505 -
  1.1506 -"----- Schalk I, p.69 Nr. 460b nonterm.SK";
  1.1507 -val t = TermC.str2term "(9*(x \<up> 2 - 8*x + 16) / (4*(y \<up> 2 - 2*y + 1))) / ((3*x - 12) / (16*y - 16))";
  1.1508 -(*val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1509 -exception Div raised
  1.1510 -
  1.1511 -BUT
  1.1512 -val t = TermC.str2term 
  1.1513 -  ("(144 + -72 * x + 9 * x \<up> 2) / (4 + -8 * y + 4 * y \<up> 2) /" ^
  1.1514 -  "((-12 + 3 * x) / (-16 + 16 * y))");
  1.1515 -NONE = cancel_p_ thy t;
  1.1516 -
  1.1517 -if UnparseC.term t = !!!!!!!!!!!!!!!!!!!!!!!!!
  1.1518 -then () else error "rational.sml: diff.behav. in norm_Rational_mg 42";
  1.1519 -*)
  1.1520 -
  1.1521 -"----- some variant of the above; was non-terminating before";
  1.1522 -val t = TermC.str2term "9*(x \<up> 2 - 8*x+16)*(16*y - 16)/(4*(y \<up> 2 - 2*y+1)*(3*x - 12))";
  1.1523 -val SOME (t , _) = rewrite_set_ thy false norm_Rational t;
  1.1524 -if UnparseC.term t = "(48 + - 12 * x) / (1 + - 1 * y)"
  1.1525 -then () else error "some variant of the above; was non-terminating before";
  1.1526 -
  1.1527 -"----- SRD Schalk I, p.70 Nr. 472a";
  1.1528 -val t = TermC.str2term ("((8*x \<up> 2 - 32*y \<up> 2) / (2*x + 4*y))  /  ((4*x - 8*y) / (x + y))");
  1.1529 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1530 -if UnparseC.term t = "x + y"
  1.1531 -then () else error "rational.sml: diff.behav. in norm_Rational_mg 43";
  1.1532 -
  1.1533 -"----- Schalk I, p.70 Nr. 478b ----- Rechenzeit: 5 sec";
  1.1534 -val t = TermC.str2term ("(a - (a*b + b \<up> 2)/(a+b))/(b+(a - b)/(1+(a+b)/(a - b))) / " ^
  1.1535 -		 "((a - a \<up> 2/(a+b))/(a+(a*b)/(a - b)))");
  1.1536 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1537 -if UnparseC.term t = "(2 * a \<up> 3 + 2 * a \<up> 2 * b) / (a \<up> 2 * b + b \<up> 3)"
  1.1538 -then () else error "rational.sml: diff.behav. in norm_Rational_mg 51";
  1.1539 -
  1.1540 -(*SRD Schalk I, p.69 Nr. 461a *)
  1.1541 -val t = TermC.str2term "(2/(x+3) + 2/(x - 3)) / (8*x/(x \<up> 2 - 9))";
  1.1542 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1543 -if UnparseC.term t = "1 / 2"
  1.1544 -then () else error "rational.sml: diff.behav. in norm_Rational_mg 44";
  1.1545 -
  1.1546 -(*SRD Schalk I, p.69 Nr. 464b *)
  1.1547 -val t = TermC.str2term "(a - a/(a - 2)) / (a + a/(a - 2))";
  1.1548 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1549 -if UnparseC.term t = "(- 3 + a) / (- 1 + a)"
  1.1550 -then () else error "rational.sml: diff.behav. in norm_Rational_mg 45";
  1.1551 -
  1.1552 -(*SRD Schalk I, p.69 Nr. 465b *)
  1.1553 -val t = TermC.str2term "((x+3*y)/9 + (4*y \<up> 2 - 9*z \<up> 2)/(16*x))   /   (x/9 + y/6 + z/4)";
  1.1554 -(* WN130911 non-termination due to non-termination of
  1.1555 -  cancel_p_ thy (TermC.str2term 
  1.1556 -    ("("(576 * x \<up> 2 + 1728 * (x * y) + 1296 * y \<up> 2 + -2916 * z \<up> 2) /" ^
  1.1557 -      "(576 * x \<up> 2 + 864 * (x * y) + 1296 * (x * z))"))
  1.1558 -
  1.1559 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1560 -if UnparseC.term t = "(4 * x + 6 * y + -9 * z) / (4 * x)"
  1.1561 -then () else error "rational.sml: diff.behav. in norm_Rational_mg 46";
  1.1562 -*)
  1.1563 -
  1.1564 -(*SRD Schalk I, p.69 Nr. 466b *)
  1.1565 -val t = TermC.str2term "((1 - 7*(x - 2)/(x \<up> 2 - 4)) / (6/(x+2))) / (3/(x+5)+30/(x \<up> 2 - 25))";
  1.1566 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1567 -if UnparseC.term t = "(25 + - 10 * x + x \<up> 2) / 18"
  1.1568 -then () else error "rational.sml: diff.behav. in norm_Rational_mg 47";
  1.1569 -
  1.1570 -(*SRD Schalk I, p.70 Nr. 469 *)
  1.1571 -val t = TermC.str2term ("3*b \<up> 2 / (4*a \<up> 2 - 8*a*b + 4*b \<up> 2) / " ^
  1.1572 -  "(a / (a \<up> 2*b - b \<up> 3)  +  (a - b) / (4*a*b \<up> 2 + 4*b \<up> 3)  -  1 / (4*b \<up> 2))");
  1.1573 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1574 -if UnparseC.term t = "- 3 * b \<up> 3 / (- 2 * a + 2 * b)"
  1.1575 -then () else error "rational.sml: diff.behav. in norm_Rational_mg 48";
  1.1576 -
  1.1577 -(*//----------------------------------TOODOO (*Rfuns revsets \<longrightarrow> broken*)
  1.1578 -"-------- me Schalk I No.186 -------------------------------------------------";
  1.1579 -"-------- me Schalk I No.186 -------------------------------------------------";
  1.1580 -"-------- me Schalk I No.186 -------------------------------------------------";
  1.1581 -val fmz = ["Term ((14 * x * y) / ( x * y ))", "normalform N"];
  1.1582 -val (dI',pI',mI') =
  1.1583 -  ("Rational",["rational", "simplification"],
  1.1584 -   ["simplification", "of_rationals"]);
  1.1585 -val p = e_pos'; val c = []; 
  1.1586 -val (p,_,f,nxt,_,pt) = CalcTreeTEST [(fmz, (dI',pI',mI'))];
  1.1587 -val (p,_,f,nxt,_,pt) = me nxt p c pt;
  1.1588 -val (p,_,f,nxt,_,pt) = me nxt p c pt;
  1.1589 -val (p,_,f,nxt,_,pt) = me nxt p c pt;
  1.1590 -val (p,_,f,nxt,_,pt) = me nxt p c pt;
  1.1591 -val (p,_,f,nxt,_,pt) = me nxt p c pt;
  1.1592 -val (p,_,f,nxt,_,pt) = me nxt p c pt;
  1.1593 -val (p,_,f,nxt,_,pt) = me nxt p c pt;
  1.1594 -val (p,_,f,nxt,_,pt) = me nxt p c pt; f2str f;
  1.1595 -val (p,_,f,nxt,_,pt) = me nxt p c pt; f2str f;
  1.1596 -val (p,_,f,nxt,_,pt) = me nxt p c pt; f2str f;(*++ for explicit script*)
  1.1597 -val (p,_,f,nxt,_,pt) = me nxt p c pt; f2str f;(*++ for explicit script*)
  1.1598 -case (f2str f, nxt) of
  1.1599 -    ("14", ("End_Proof'", _)) => ()
  1.1600 -  | _ => error "rational.sml diff.behav. in me Schalk I No.186";
  1.1601 -  \\----------------------------------TOODOO (*Rfuns revsets \<longrightarrow> broken*)*)
  1.1602 -
  1.1603 -(*//----------------------------------TOODOO (*Rfuns revsets \<longrightarrow> broken*)
  1.1604 -"-------- interSteps ..Simp_Rat_Double_No-1.xml ------------------------------";
  1.1605 -"-------- interSteps ..Simp_Rat_Double_No-1.xml ------------------------------";
  1.1606 -"-------- interSteps ..Simp_Rat_Double_No-1.xml ------------------------------";
  1.1607 -reset_states ();
  1.1608 -CalcTree [(["Term (((2 - x)/(2*a)) / (2*a/(x - 2)))", "normalform N"], 
  1.1609 -  ("Rational", ["rational", "simplification"], ["simplification", "of_rationals"]))];
  1.1610 -Iterator 1;
  1.1611 -moveActiveRoot 1;
  1.1612 -autoCalculate 1 CompleteCalc;
  1.1613 -val ((pt, p), _) = get_calc 1; 
  1.1614 -(*
  1.1615 -Test_Tool.show_pt pt;
  1.1616 -[
  1.1617 -(([], Frm), Simplify ((2 - x) / (2 * a) / (2 * a / (x - 2)))),
  1.1618 -(([1], Frm), (2 - x) / (2 * a) / (2 * a / (x - 2))),
  1.1619 -(([1], Res), (2 + -1 * x) / (2 * a) / (2 * a / (x + -1 * 2))),
  1.1620 -(([2], Res), (2 + -1 * x) / (2 * a) / (2 * a / (-2 + x))),
  1.1621 -(([3], Res), (2 + -1 * x) * (-2 + x) / (2 * a * (2 * a))),
  1.1622 -(([4], Res), (-4 + 4 * x + -1 * x \<up> 2) / (4 * a \<up> 2)),
  1.1623 -(([], Res), (-4 + 4 * x + -1 * x \<up> 2) / (4 * a \<up> 2))] 
  1.1624 -*)
  1.1625 -interSteps 1 ([1], Res);
  1.1626 -val ((pt, p), _) = get_calc 1; 
  1.1627 -(*Test_Tool.show_pt pt;
  1.1628 -[
  1.1629 -(([], Frm), Simplify ((2 - x) / (2 * a) / (2 * a / (x - 2)))),
  1.1630 -(([1], Frm), (2 - x) / (2 * a) / (2 * a / (x - 2))),
  1.1631 -(([1,1], Frm), (2 - x) / (2 * a) / (2 * a / (x - 2))),
  1.1632 -(([1,1], Res), (2 - x) / (2 * a) / (2 * a / (x + -1 * 2))),
  1.1633 -(([1,2], Res), (2 + -1 * x) / (2 * a) / (2 * a / (x + -1 * 2))),
  1.1634 -(([1], Res), (2 + -1 * x) / (2 * a) / (2 * a / (x + -1 * 2))),
  1.1635 -(([2], Res), (2 + -1 * x) / (2 * a) / (2 * a / (-2 + x))),
  1.1636 -(([3], Res), (2 + -1 * x) * (-2 + x) / (2 * a * (2 * a))),
  1.1637 -(([4], Res), (-4 + 4 * x + -1 * x \<up> 2) / (4 * a \<up> 2)),
  1.1638 -(([], Res), (-4 + 4 * x + -1 * x \<up> 2) / (4 * a \<up> 2))] 
  1.1639 -*)
  1.1640 -val (t, asm) = get_obj g_result pt [1, 1];
  1.1641 -if UnparseC.term t = "(2 - x) / (2 * a) / (2 * a / (x + -1 * 2))" andalso UnparseC.terms asm = "[]"
  1.1642 -then () else error "2nd interSteps ..Simp_Rat_Double_No-1 changed on [1, 1]";
  1.1643 -val (t, asm) = get_obj g_result pt [1, 2];
  1.1644 -if UnparseC.term t = "(2 + -1 * x) / (2 * a) / (2 * a / (x + -1 * 2))" andalso UnparseC.terms asm = "[]"
  1.1645 -then () else error "3rd interSteps ..Simp_Rat_Double_No-1 changed on [1, 2]";
  1.1646 -  \\----------------------------------TOODOO (*Rfuns revsets \<longrightarrow> broken*)*)
  1.1647 -
  1.1648 -
  1.1649 -(*//----------------------------------TOODOO (*Rfuns revsets \<longrightarrow> broken*)
  1.1650 -"-------- interSteps ..Simp_Rat_Cancel_No-1.xml ------------------------------";
  1.1651 -"-------- interSteps ..Simp_Rat_Cancel_No-1.xml ------------------------------";
  1.1652 -"-------- interSteps ..Simp_Rat_Cancel_No-1.xml ------------------------------";
  1.1653 -reset_states ();
  1.1654 -CalcTree [(["Term ((a^2 + -1*b^2) / (a^2 + -2*a*b + b^2))", "normalform N"], 
  1.1655 -  ("Rational", ["rational", "simplification"], ["simplification", "of_rationals"]))];
  1.1656 -Iterator 1;
  1.1657 -moveActiveRoot 1;
  1.1658 -autoCalculate 1 CompleteCalc;
  1.1659 -val ((pt, p), _) = get_calc 1;
  1.1660 -(*Test_Tool.show_pt pt;
  1.1661 -[
  1.1662 -(([], Frm), Simplify ((a \<up> 2 + -1 * b \<up> 2) / (a \<up> 2 + -2 * a * b + b \<up> 2))),
  1.1663 -(([1], Frm), (a \<up> 2 + -1 * b \<up> 2) / (a \<up> 2 + -2 * a * b + b \<up> 2)),
  1.1664 -(([1], Res), (a \<up> 2 + -1 * b \<up> 2) / (a \<up> 2 + -2 * (a * b) + b \<up> 2)),
  1.1665 -(([2], Res), (a + b) / (a + -1 * b)),
  1.1666 -(([], Res), (a + b) / (a + -1 * b))] 
  1.1667 -*)
  1.1668 -interSteps 1 ([2], Res);
  1.1669 -val ((pt, p), _) = get_calc 1;
  1.1670 -(*Test_Tool.show_pt pt;
  1.1671 -[
  1.1672 -(([], Frm), Simplify ((a \<up> 2 + -1 * b \<up> 2) / (a \<up> 2 + -2 * a * b + b \<up> 2))),
  1.1673 -(([1], Frm), (a \<up> 2 + -1 * b \<up> 2) / (a \<up> 2 + -2 * a * b + b \<up> 2)),
  1.1674 -(([1], Res), (a \<up> 2 + -1 * b \<up> 2) / (a \<up> 2 + -2 * (a * b) + b \<up> 2)),
  1.1675 -(([2,1], Frm), (a \<up> 2 + -1 * b \<up> 2) / (a \<up> 2 + -2 * (a * b) + b \<up> 2)),
  1.1676 -(([2,1], Res), (a + b) / (a + -1 * b)),
  1.1677 -(([2], Res), (a + b) / (a + -1 * b)),
  1.1678 -(([], Res), (a + b) / (a + -1 * b))] 
  1.1679 -*)
  1.1680 -interSteps 1 ([2,1],Res);
  1.1681 -val ((pt, p), _) = get_calc 1; 
  1.1682 -(*Test_Tool.show_pt pt;
  1.1683 -[
  1.1684 -(([], Frm), Simplify ((a \<up> 2 + -1 * b \<up> 2) / (a \<up> 2 + -2 * a * b + b \<up> 2))),
  1.1685 -(([1], Frm), (a \<up> 2 + -1 * b \<up> 2) / (a \<up> 2 + -2 * a * b + b \<up> 2)),
  1.1686 -(([1], Res), (a \<up> 2 + -1 * b \<up> 2) / (a \<up> 2 + -2 * (a * b) + b \<up> 2)),
  1.1687 -(([2,1], Frm), (a \<up> 2 + -1 * b \<up> 2) / (a \<up> 2 + -2 * (a * b) + b \<up> 2)),
  1.1688 -(([2,1,1], Frm), (a \<up> 2 + -1 * b \<up> 2) / (a \<up> 2 + -2 * (a * b) + b \<up> 2)),
  1.1689 -(([2,1,1], Res), (a \<up> 2 + -1 * (a * b) + a * b + -1 * b \<up> 2) /
  1.1690 -(a \<up> 2 + -2 * (a * b) + 1 * b \<up> 2)),
  1.1691 -(([2,1,2], Res), (a \<up> 2 + -1 * (a * b) + a * b + -1 * b \<up> 2) /
  1.1692 -(a \<up> 2 + -2 * (a * b) + -1 \<up> 2 * b \<up> 2)),
  1.1693 -(([2,1,3], Res), (a \<up> 2 + -1 * (a * b) + a * b + -1 * b \<up> 2) /
  1.1694 -(a \<up> 2 + -2 * (a * b) + (-1 * b) \<up> 2)),
  1.1695 -(([2,1,4], Res), (a * a + -1 * (a * b) + a * b + -1 * b \<up> 2) /
  1.1696 -(a \<up> 2 + -2 * (a * b) + (-1 * b) \<up> 2)),
  1.1697 -(([2,1,5], Res), (a * a + -1 * (a * b) + a * b + -1 * (b * b)) /
  1.1698 -(a \<up> 2 + -2 * (a * b) + (-1 * b) \<up> 2)),
  1.1699 -(([2,1,6], Res), (a * a + -1 * (a * b) + a * b + -1 * (b * b)) /
  1.1700 -(a \<up> 2 + -1 * (2 * (a * b)) + (-1 * b) \<up> 2)),
  1.1701 -(([2,1,7], Res), (a * a + a * (-1 * b) + (b * a + b * (-1 * b))) /
  1.1702 -(a \<up> 2 + 2 * (a * (-1 * b)) + (-1 * b) \<up> 2)),
  1.1703 -(([2,1,8], Res), (a * a + a * (-1 * b) + (b * a + b * (-1 * b))) /
  1.1704 -(a \<up> 2 + 2 * a * (-1 * b) + (-1 * b) \<up> 2)),
  1.1705 -(([2,1,9], Res), (a * (a + -1 * b) + (b * a + b * (-1 * b))) /
  1.1706 -(a \<up> 2 + 2 * a * (-1 * b) + (-1 * b) \<up> 2)),
  1.1707 -(([2,1,10], Res), (a * (a + -1 * b) + b * (a + -1 * b)) /
  1.1708 -(a \<up> 2 + 2 * a * (-1 * b) + (-1 * b) \<up> 2)),
  1.1709 -(([2,1,11], Res), (a + b) * (a + -1 * b) / (a \<up> 2 + 2 * a * (-1 * b) + (-1 * b) \<up> 2)),
  1.1710 -(([2,1,12], Res), (a + b) * (a + -1 * b) / ((a + -1 * b) * (a + -1 * b))),
  1.1711 -(([2,1,13], Res), (a + b) / (a + -1 * b)),
  1.1712 -(([2,1], Res), (a + b) / (a + -1 * b)),
  1.1713 -(([2], Res), (a + b) / (a + -1 * b)),
  1.1714 -(([], Res), (a + b) / (a + -1 * b))] 
  1.1715 -*)
  1.1716 -val newnds = children (get_nd pt [2,1]) (*see "fun detailrls"*);
  1.1717 -if length newnds = 13 then () else error "rational.sml: interSteps cancel_p rev_rew_p";
  1.1718 -
  1.1719 -val p = ([2,1,9],Res);
  1.1720 -getTactic 1 p;
  1.1721 -val (_, tac, _) = ME_Misc.pt_extract (pt, p);
  1.1722 -case tac of SOME (Rewrite ("sym_distrib_left", _)) => ()
  1.1723 -| _ => error "rational.sml: getTactic, sym_real_plus_binom_times1";
  1.1724 -  \\----------------------------------TOODOO (*Rfuns revsets \<longrightarrow> broken*)*)
  1.1725 -
  1.1726 -
  1.1727 -"-------- investigate rulesets for cancel_p ----------------------------------";
  1.1728 -"-------- investigate rulesets for cancel_p ----------------------------------";
  1.1729 -"-------- investigate rulesets for cancel_p ----------------------------------";
  1.1730 -val thy = @{theory "Rational"};
  1.1731 -val t = TermC.str2term "(a \<up> 2 + -1*b \<up> 2) / (a \<up> 2 + -2*a*b + b \<up> 2)";
  1.1732 -val tt = TermC.str2term "(1 * a + 1 * b) * (1 * a + -1 * b)"(*numerator only*);
  1.1733 -
  1.1734 -"----- with rewrite_set_";
  1.1735 -val SOME (tt',asm) = rewrite_set_ thy false make_polynomial tt;
  1.1736 -if UnparseC.term tt'= "a \<up> 2 + - 1 * b \<up> 2" then () else error "rls chancel_p 1";
  1.1737 -val tt = TermC.str2term "((1 * a + -1 * b) * (1 * a + -1 * b))"(*denominator only*);
  1.1738 -val SOME (tt',asm) = rewrite_set_ thy false make_polynomial tt;
  1.1739 -if UnparseC.term tt' = "a \<up> 2 + - 2 * a * b + b \<up> 2" then () else error "rls chancel_p 2";
  1.1740 -
  1.1741 -"----- with Derive.do_one; WN1130912 not investigated further, will be discontinued";
  1.1742 -val SOME (tt, _) = factout_p_ thy t; 
  1.1743 -if UnparseC.term tt = "(a + b) * (a + - 1 * b) / ((a + - 1 * b) * (a + - 1 * b))"
  1.1744 -then () else error "rls chancel_p 3";
  1.1745 -
  1.1746 -"--- with simpler ruleset";
  1.1747 -val {rules, rew_ord= (_, ro), ...} = Rule_Set.rep (assoc_rls "rev_rew_p");
  1.1748 -val der = Derive.do_one thy Atools_erls rules ro NONE tt;
  1.1749 -if length der = 12 then () else error "WN1130912 rls chancel_p 4";
  1.1750 -(*default_print_depth 99;*) writeln (Derive.deriv2str der); (*default_print_depth 3;*)
  1.1751 -
  1.1752 -(*default_print_depth 99;*) map (UnparseC.term o #1) der; (*default_print_depth 3;*)
  1.1753 -"...,(-1 * b \<up> 2 + a \<up> 2) / (-2 * (a * b) + a \<up> 2 + (-1 * b) \<up> 2) ]";
  1.1754 -(*default_print_depth 99;*) map (Rule.to_string o #2) der; (*default_print_depth 3;*)
  1.1755 -(*default_print_depth 99;*) map (UnparseC.term o #1 o #3) der; (*default_print_depth 3;*)
  1.1756 -
  1.1757 -val der = Derive.do_one thy Atools_erls rules ro NONE 
  1.1758 -	(TermC.str2term "(1 * a + 1 * b) * (1 * a + -1 * b)");
  1.1759 -(*default_print_depth 99;*) writeln (Derive.deriv2str der); (*default_print_depth 3;*)
  1.1760 -
  1.1761 -val {rules, rew_ord=(_,ro),...} = Rule_Set.rep (assoc_rls "rev_rew_p");
  1.1762 -val der = Derive.do_one thy Atools_erls rules ro NONE 
  1.1763 -	(TermC.str2term "(1 * a + -1 * b) * (1 * a + -1 * b)");
  1.1764 -(*default_print_depth 99;*) writeln (Derive.deriv2str der); (*default_print_depth 3;*)
  1.1765 -(*default_print_depth 99;*) map (UnparseC.term o #1) der; (*default_print_depth 3;*)
  1.1766 -(*WN060829 ...postponed*)
  1.1767 -
  1.1768 -
  1.1769 -"-------- fun eval_get_denominator -------------------------------------------";
  1.1770 -"-------- fun eval_get_denominator -------------------------------------------";
  1.1771 -"-------- fun eval_get_denominator -------------------------------------------";
  1.1772 -val thy = @{theory Isac_Knowledge};
  1.1773 -val t = Thm.term_of (the (TermC.parse thy "get_denominator ((a +x)/b)"));
  1.1774 -val SOME (_, t') = eval_get_denominator "" 0 t thy;
  1.1775 -if UnparseC.term t' = "get_denominator ((a + x) / b) = b"
  1.1776 -then () else error "get_denominator ((a + x) / b) = b"
  1.1777 -
  1.1778 -
  1.1779 -"-------- several errpats in complicated term --------------------------------";
  1.1780 -"-------- several errpats in complicated term --------------------------------";
  1.1781 -"-------- several errpats in complicated term --------------------------------";
  1.1782 -(*WN12xxxx TODO: instead of Gabriella's example here (27.Jul.12) find a simpler one
  1.1783 -  WN130912: kept this test, although not clear what for*)
  1.1784 -reset_states ();
  1.1785 -CalcTree [(["Term ((5*b + 25)/(a^2 - b^2) * (a - b)/(5*b))", "normalform N"], 
  1.1786 -  ("Rational", ["rational", "simplification"], ["simplification", "of_rationals"]))];
  1.1787 -Iterator 1;
  1.1788 -moveActiveRoot 1;
  1.1789 -autoCalculate 1 CompleteCalc;
  1.1790 -val ((pt, p), _) = get_calc 1;
  1.1791 -(*Test_Tool.show_pt pt;
  1.1792 -[
  1.1793 -(([], Frm), Simplify ((5 * b + 25) / (a \<up> 2 - b \<up> 2) * (a - b) / (5 * b))),
  1.1794 -(([1], Frm), (5 * b + 25) / (a \<up> 2 - b \<up> 2) * (a - b) / (5 * b)),
  1.1795 -(([1], Res), (5 * b + 25) / (a \<up> 2 + -1 * b \<up> 2) * (a + -1 * b) / (5 * b)),
  1.1796 -(([2], Res), (5 * b + 25) * (a + -1 * b) / (a \<up> 2 + -1 * b \<up> 2) / (5 * b)),
  1.1797 -(([3], Res), (25 * a + -25 * b + 5 * (a * b) + -5 * b \<up> 2) / (a \<up> 2 + -1 * b \<up> 2) /
  1.1798 -(5 * b)),
  1.1799 -(([4], Res), (25 + 5 * b) / (a + b) / (5 * b)),
  1.1800 -(([5], Res), (25 + 5 * b) / ((a + b) * (5 * b))),
  1.1801 -(([6], Res), (25 + 5 * b) / (5 * (a * b) + 5 * b \<up> 2)),
  1.1802 -(([7], Res), (5 + b) / (a * b + b \<up> 2)),
  1.1803 -(([], Res), (5 + b) / (a * b + b \<up> 2))] *)
  1.1804 -
  1.1805 -
  1.1806 -"-------- WN1309xx non-terminating rls norm_Rational -------------------------";
  1.1807 -"-------- WN1309xx non-terminating rls norm_Rational -------------------------";
  1.1808 -"-------- WN1309xx non-terminating rls norm_Rational -------------------------";
  1.1809 -(*------- Schalk I, p.70 Nr. 480b; a/b : c/d translated to a/b * d/c*)
  1.1810 -val t = TermC.str2term 
  1.1811 -  ("((12*x*y / (9*x \<up> 2 - y \<up> 2))  /  (1 / (3*x - y) \<up> 2 - 1 / (3*x + y) \<up> 2))  *  " ^
  1.1812 -	"((1/(x - 5*y) \<up> 2  -  1/(x + 5*y) \<up> 2)  /  (20*x*y / (x \<up> 2 - 25*y \<up> 2)))");
  1.1813 -
  1.1814 -(*1st factor separately simplified *)
  1.1815 -val t = TermC.str2term "((12*x*y / (9*x \<up> 2 - y \<up> 2))  /  (1 / (3*x - y) \<up> 2 - 1 / (3*x + y) \<up> 2))";
  1.1816 -val SOME (t', _) = rewrite_set_ thy false norm_Rational t; 
  1.1817 -if UnparseC.term t' = "(- 9 * x \<up> 2 + y \<up> 2) / - 1" then () else error "Nr. 480b lhs changed";
  1.1818 -(*2nd factor separately simplified *)
  1.1819 -val t = TermC.str2term "((1/(x - 5*y) \<up> 2  -  1/(x + 5*y) \<up> 2)  /  (20*x*y / (x \<up> 2 - 25*y \<up> 2)))";
  1.1820 -val SOME (t',_) = rewrite_set_ thy false norm_Rational t; UnparseC.term t';
  1.1821 -if UnparseC.term t' = "- 1 / (- 1 * x \<up> 2 + 25 * y \<up> 2)" then () else error "Nr. 480b rhs changed";
  1.1822 -
  1.1823 -"-------- Schalk I, p.70 Nr. 477a: terms are exploding ?!?";
  1.1824 -val t = TermC.str2term ("b*y/(b - 2*y)/((b \<up> 2 - y \<up> 2)/(b+2*y))  /" ^
  1.1825 -		 "(b \<up> 2*y + b*y \<up> 2) * (a+x) \<up> 2  /  ((b \<up> 2 - 4*y \<up> 2) * (a+2*x) \<up> 2)");
  1.1826 -(*val SOME (t',_) = rewrite_set_ thy false norm_Rational t;
  1.1827 -:
  1.1828 -###  rls: cancel_p on: (a \<up> 2 * (b * y) + 2 * (a * (b * (x * y))) + b * (x \<up> 2 * y)) /
  1.1829 -(b + -2 * y) /
  1.1830 -((b \<up> 2 + -1 * y \<up> 2) / (b + 2 * y)) /
  1.1831 -(b \<up> 2 * y + b * y \<up> 2) /
  1.1832 -(a \<up> 2 * b \<up> 2 + -4 * (a \<up> 2 * y \<up> 2) + 4 * (a * (b \<up> 2 * x)) +
  1.1833 - -16 * (a * (x * y \<up> 2)) +
  1.1834 - 4 * (b \<up> 2 * x \<up> 2) +
  1.1835 - -16 * (x \<up> 2 * y \<up> 2)) 
  1.1836 -exception Div raised
  1.1837 -
  1.1838 -BUT
  1.1839 -val t = TermC.str2term 
  1.1840 -  ("(a \<up> 2 * (b * y) + 2 * (a * (b * (x * y))) + b * (x \<up> 2 * y)) /" ^
  1.1841 -  "(b + -2 * y) /" ^
  1.1842 -  "((b \<up> 2 + -1 * y \<up> 2) / (b + 2 * y)) /" ^
  1.1843 -  "(b \<up> 2 * y + b * y \<up> 2) /" ^
  1.1844 -  "(a \<up> 2 * b \<up> 2 + -4 * (a \<up> 2 * y \<up> 2) + 4 * (a * (b \<up> 2 * x)) +" ^
  1.1845 -  "-16 * (a * (x * y \<up> 2)) +" ^
  1.1846 -  "4 * (b \<up> 2 * x \<up> 2) +" ^
  1.1847 -  "-16 * (x \<up> 2 * y \<up> 2))");
  1.1848 -NONE = cancel_p_ thy t;
  1.1849 -*)
  1.1850 -
  1.1851 -(*------- Schalk I, p.70 Nr. 476b in 2003 this worked using 10 sec. *)
  1.1852 -val t = TermC.str2term 
  1.1853 -  ("((a \<up> 2 - b \<up> 2)/(2*a*b) + 2*a*b/(a \<up> 2 - b \<up> 2))  /  ((a \<up> 2 + b \<up> 2)/(2*a*b) + 1)    / " ^
  1.1854 -   "((a \<up> 2 + b \<up> 2) \<up> 2  /  (a + b) \<up> 2)");
  1.1855 -(* Rewrite.trace_on := true;
  1.1856 -rewrite_set_ thy false norm_Rational t;
  1.1857 -:
  1.1858 -####  rls: cancel_p on: (2 * (a \<up> 7 * b) + 4 * (a \<up> 6 * b \<up> 2) + 6 * (a \<up> 5 * b \<up> 3) +
  1.1859 - 8 * (a \<up> 4 * b \<up> 4) +
  1.1860 - 6 * (a \<up> 3 * b \<up> 5) +
  1.1861 - 4 * (a \<up> 2 * b \<up> 6) +
  1.1862 - 2 * (a * b \<up> 7)) /
  1.1863 -(2 * (a \<up> 9 * b) + 4 * (a \<up> 8 * b \<up> 2) +
  1.1864 - 2 * (2 * (a \<up> 7 * b \<up> 3)) +
  1.1865 - 4 * (a \<up> 6 * b \<up> 4) +
  1.1866 - -4 * (a \<up> 4 * b \<up> 6) +
  1.1867 - -4 * (a \<up> 3 * b \<up> 7) +
  1.1868 - -4 * (a \<up> 2 * b \<up> 8) +
  1.1869 - -2 * (a * b \<up> 9))
  1.1870 -
  1.1871 -if UnparseC.term t = "1 / (a \<up> 2 + -1 * b \<up> 2)" then ()
  1.1872 -else error "rational.sml: diff.behav. in norm_Rational_mg 49";
  1.1873 -*)
  1.1874 -
  1.1875 -"-------- Schalk I, p.70 Nr. 480a: terms are exploding ?!?";
  1.1876 -val t = TermC.str2term ("(1/x + 1/y + 1/z)  /  (1/x - 1/y - 1/z)  /  " ^
  1.1877 -  "(2*x \<up> 2 / (x \<up> 2 - z \<up> 2) / (x / (x + z)  +  x / (x - z)))");
  1.1878 -(* Rewrite.trace_on := true;
  1.1879 -rewrite_set_ thy false norm_Rational t;
  1.1880 -:
  1.1881 -####  rls: cancel_p on: (2 * (x \<up> 6 * (y \<up> 2 * z)) + 2 * (x \<up> 6 * (y * z \<up> 2)) +
  1.1882 - 2 * (x \<up> 5 * (y \<up> 2 * z \<up> 2)) +
  1.1883 - -2 * (x \<up> 4 * (y \<up> 2 * z \<up> 3)) +
  1.1884 - -2 * (x \<up> 4 * (y * z \<up> 4)) +
  1.1885 - -2 * (x \<up> 3 * (y \<up> 2 * z \<up> 4))) /
  1.1886 -(-2 * (x \<up> 6 * (y \<up> 2 * z)) + -2 * (x \<up> 6 * (y * z \<up> 2)) +
  1.1887 - 2 * (x \<up> 5 * (y \<up> 2 * z \<up> 2)) +
  1.1888 - 2 * (x \<up> 4 * (y \<up> 2 * z \<up> 3)) +
  1.1889 - 2 * (x \<up> 4 * (y * z \<up> 4)) +
  1.1890 - -2 * (x \<up> 3 * (y \<up> 2 * z \<up> 4)))
  1.1891 -*)
  1.1892 -
  1.1893 -"-------- Schalk I, p.60 Nr. 215d: terms are exploding, internal loop does not terminate";
  1.1894 -val t = TermC.str2term "(a-b) \<up> 3 * (x+y) \<up> 4 / ((x+y) \<up> 2 * (a-b) \<up> 5)";
  1.1895 -(* Kein Wunder, denn Z???ler und Nenner extra als Polynom dargestellt ergibt:
  1.1896 -
  1.1897 -val t = TermC.str2term "(a-b) \<up> 3 * (x+y) \<up> 4";
  1.1898 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1899 -UnparseC.term t;
  1.1900 -"a \<up> 3 * x \<up> 4 + 4 * a \<up> 3 * x \<up> 3 * y +6 * a \<up> 3 * x \<up> 2 * y \<up> 2 +4 * a \<up> 3 * x * y \<up> 3 +a \<up> 3 * y \<up> 4 +-3 * a \<up> 2 * b * x \<up> 4 +-12 * a \<up> 2 * b * x \<up> 3 * y +-18 * a \<up> 2 * b * x \<up> 2 * y \<up> 2 +-12 * a \<up> 2 * b * x * y \<up> 3 +-3 * a \<up> 2 * b * y \<up> 4 +3 * a * b \<up> 2 * x \<up> 4 +12 * a * b \<up> 2 * x \<up> 3 * y +18 * a * b \<up> 2 * x \<up> 2 * y \<up> 2 +12 * a * b \<up> 2 * x * y \<up> 3 +3 * a * b \<up> 2 * y \<up> 4 +-1 * b \<up> 3 * x \<up> 4 +-4 * b \<up> 3 * x \<up> 3 * y +-6 * b \<up> 3 * x \<up> 2 * y \<up> 2 +-4 * b \<up> 3 * x * y \<up> 3 +-1 * b \<up> 3 * y \<up> 4";
  1.1901 -val t = TermC.str2term "((x+y) \<up> 2 * (a-b) \<up> 5)";
  1.1902 -val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1903 -UnparseC.term t;
  1.1904 -"a \<up> 5 * x \<up> 2 + 2 * a \<up> 5 * x * y + a \<up> 5 * y \<up> 2 +-5 * a \<up> 4 * b * x \<up> 2 +-10 * a \<up> 4 * b * x * y +-5 * a \<up> 4 * b * y \<up> 2 +10 * a \<up> 3 * b \<up> 2 * x \<up> 2 +20 * a \<up> 3 * b \<up> 2 * x * y +10 * a \<up> 3 * b \<up> 2 * y \<up> 2 +-10 * a \<up> 2 * b \<up> 3 * x \<up> 2 +-20 * a \<up> 2 * b \<up> 3 * x * y +-10 * a \<up> 2 * b \<up> 3 * y \<up> 2 +5 * a * b \<up> 4 * x \<up> 2 +10 * a * b \<up> 4 * x * y +5 * a * b \<up> 4 * y \<up> 2 +-1 * b \<up> 5 * x \<up> 2 +-2 * b \<up> 5 * x * y +-1 * b \<up> 5 * y \<up> 2";
  1.1905 -
  1.1906 -anscheinend macht dem Rechner das Krzen diese Bruches keinen Spass mehr ...*)
  1.1907 -
  1.1908 -"-------- Schalk I, p.70 Nr. 480b: terms are exploding, Rewrite.trace_on stops at";
  1.1909 -val t = TermC.str2term ("((12*x*y/(9*x \<up> 2 - y \<up> 2))/" ^
  1.1910 -		 "(1/(3*x - y) \<up> 2 - 1/(3*x + y) \<up> 2)) *" ^
  1.1911 -		 "(1/(x - 5*y) \<up> 2 - 1/(x + 5*y) \<up> 2)/" ^
  1.1912 -		 "(20*x*y/(x \<up> 2 - 25*y \<up> 2))");
  1.1913 -(*val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1.1914 -:
  1.1915 -####  rls: cancel_p on: (19440 * (x \<up> 8 * y \<up> 2) + -490320 * (x \<up> 6 * y \<up> 4) +
  1.1916 - 108240 * (x \<up> 4 * y \<up> 6) +
  1.1917 - -6000 * (x \<up> 2 * y \<up> 8)) /
  1.1918 -(2160 * (x \<up> 8 * y \<up> 2) + -108240 * (x \<up> 6 * y \<up> 4) +
  1.1919 - 1362000 * (x \<up> 4 * y \<up> 6) +
  1.1920 - -150000 * (x \<up> 2 * y \<up> 8))
  1.1921 -*)
  1.1922 -