test/Tools/isac/Knowledge/rational.sml
author wneuper <walther.neuper@jku.at>
Sat, 03 Jul 2021 16:21:07 +0200
changeset 60318 e6e7a9b9ced7
parent 60270 844610c5c943
child 60323 c67d7def5a51
permissions -rw-r--r--
//test/../rewrite.sml,poly.sml WORK
     1 (* Title: tests for rationals
     2    Author: Walther Neuper
     3    Use is subject to license terms.
     4 *)
     5 
     6 "-----------------------------------------------------------------------------";
     7 "-----------------------------------------------------------------------------";
     8 "table of contents -----------------------------------------------------------";
     9 "-----------------------------------------------------------------------------";
    10 "-------- fun poly_of_term ---------------------------------------------------";
    11 "-------- fun is_poly --------------------------------------------------------";
    12 "-------- fun term_of_poly ---------------------------------------------------";
    13 "-------- integration lev.1 fun factout_p_ -----------------------------------";
    14 "-------- integration lev.1 fun cancel_p_ ------------------------------------";
    15 "-------- integration lev.1 fun common_nominator_p_ --------------------------";
    16 "-------- integration lev.1 fun add_fraction_p_ ------------------------------";
    17 "Rfuns-------- and app_rev ...traced down from rewrite_set_ until prepats ---------";
    18 "Rfuns-------- fun rewrite_set_ cancel_p downto fun gcd_poly ----------------------";
    19 "-------- rls norm_Rational downto fun gcd_poly ------------------------------";
    20 "Rfuns-------- rls norm_Rational downto fun add_fraction_p_ -----------------------";
    21 "----------- rewrite_set_ Partial_Fractions norm_Rational --------------------------------------";
    22 "----------- fun check_frac_sum with Free A and Const AA ---------------------------------------";
    23 "----------- fun cancel_p with Const AA --------------------------------------------------------";
    24 "-------- rewrite_set_ cancel_p from: Mathematik 1 Schalk Reniets Verlag -----";
    25 "-------- rewrite_set_ add_fractions_p from: Mathematik 1 Schalk -------------";
    26 "-------- integration lev.1 -- lev.5: cancel_p_ & add_fractions_p_ -----------";
    27 "Rfuns-------- reverse rewrite ----------------------------------------------------";
    28 "Rfuns-------- 'reverse-ruleset' cancel_p -----------------------------------------";
    29 "-------- investigate rls norm_Rational --------------------------------------";
    30 "-------- examples: rls norm_Rational ----------------------------------------";
    31 "-------- rational numerals --------------------------------------------------";
    32 "-------- examples cancellation from: Mathematik 1 Schalk --------------------";
    33 "-------- examples common denominator from: Mathematik 1 Schalk --------------";
    34 "-------- examples multiply and cancel from: Mathematik 1 Schalk -------------";
    35 "-------- examples common denominator and multiplication from: Schalk --------";
    36 "-------- examples double fractions from: Mathematik 1 Schalk ----------------";
    37 "-------- me Schalk I No.186 -------------------------------------------------";
    38 "-------- interSteps ..Simp_Rat_Double_No-1.xml ------------------------------";
    39 "-------- interSteps ..Simp_Rat_Cancel_No-1.xml ------------------------------";
    40 "-------- investigate rulesets for cancel_p ----------------------------------";
    41 "-------- fun eval_get_denominator -------------------------------------------";
    42 "-------- several errpats in complicated term --------------------------------";
    43 "-------- WN1309xx non-terminating rls norm_Rational -------------------------";
    44 "-----------------------------------------------------------------------------";
    45 "-----------------------------------------------------------------------------";
    46 
    47 
    48 "-------- fun poly_of_term ---------------------------------------------------";
    49 "-------- fun poly_of_term ---------------------------------------------------";
    50 "-------- fun poly_of_term ---------------------------------------------------";
    51 val thy = @{theory Partial_Fractions};
    52 val ctxt = Proof_Context.init_global @{theory}
    53 val vs = TermC.vars_of (the (parseNEW ctxt "12 * x \<up> 3 * y \<up> 4 * z \<up> 6"));
    54 
    55 if poly_of_term vs (TermC.str2term "12::real") = SOME [(12, [0, 0, 0])]
    56 then () else error "poly_of_term 1 changed";
    57 
    58 if poly_of_term vs (TermC.str2term "x::real") = SOME [(1, [1, 0, 0])]
    59 then () else error "poly_of_term 2 changed";
    60 
    61 (*//---------------------------- removed error -----------------------------------------------\\*)
    62 if         poly_of_term vs (TermC.str2term "12 * x \<up> 3") = SOME [(12, [3, 0, 0])]
    63 then () else error "poly_of_term 3 changed";
    64 "~~~~~ fun poly_of_term , args:"; val (vs, t) =
    65   (vs, (TermC.str2term "12 * x \<up> 3"));
    66 
    67            monom_of_term vs (1, replicate (length vs) 0) t;(*poly malformed 1 with x \<up> 3*)
    68 "~~~~~ fun monom_of_term , args:"; val (vs, (c, es), (Const ("Groups.times_class.times", _) $ m1 $ m2)) =
    69   (vs, (1, replicate (length vs) 0), t);
    70     val (c', es') =
    71 
    72            monom_of_term vs (c, es) m1;
    73 "~~~~~ fun monom_of_term , args:"; val (vs, (c, es), (Const ("Transcendental.powr", _) $ (t as Free _) $ (Const ("Num.numeral_class.numeral", _) $ num)) ) =
    74   (vs, (c', es'), m2);
    75 (*+*)c = 12;
    76 (*+*)(num |> HOLogic.dest_numeral |> list_update es (find_index (curry op = t) vs)) = [3, 0, 0];
    77 
    78 if (c, num |> HOLogic.dest_numeral |> list_update es (find_index (curry op = t) vs)) = (12, [3, 0, 0])
    79 then () else error "monom_of_term (powr): return value CHANGED";
    80 (*\\---------------------------- removed error -----------------------------------------------//*)
    81 
    82 if poly_of_term vs (TermC.str2term "12 * x \<up> 3 * y \<up> 4 * z \<up> 6") = SOME [(12, [3, 4, 6])]
    83 then () else error "poly_of_term 4 changed";
    84 
    85 if poly_of_term vs (TermC.str2term "1 + 2 * x \<up> 3 * y \<up> 4 * z \<up> 6 + y") =
    86   SOME [(1, [0, 0, 0]), (1, [0, 1, 0]), (2, [3, 4, 6])]
    87 then () else error "poly_of_term 5 changed";
    88 
    89 (*poly_of_term is quite liberal:*)
    90 (*the coefficient may be somewhere, the order of variables and the parentheses 
    91   within a monomial are arbitrary*)
    92 if poly_of_term vs (TermC.str2term "y \<up> 4 * (x \<up> 3 * 12 * z \<up> 6)") = SOME [(12, [3, 4, 6])]
    93 then () else error "poly_of_term 6 changed";
    94 
    95 (*there may even be more than 1 coefficient:*)
    96 if poly_of_term vs (TermC.str2term "2 * y \<up> 4 * (x \<up> 3 * 6 * z \<up> 6)") = SOME [(12, [3, 4, 6])]
    97 then () else error "poly_of_term 7 changed";
    98 
    99 (*the order and the parentheses within monomials are arbitrary:*)
   100 if poly_of_term vs (TermC.str2term "2 * x \<up> 3 * y \<up> 4 * z \<up> 6 + (7 * y \<up> 8 + 1)")
   101   = SOME [(1, [0, 0, 0]), (7, [0, 8, 0]), (2, [3, 4, 6])]
   102 then () else error "poly_of_term 8 changed";
   103 
   104 
   105 "-------- fun is_poly --------------------------------------------------------";
   106 "-------- fun is_poly --------------------------------------------------------";
   107 "-------- fun is_poly --------------------------------------------------------";
   108 if is_poly (TermC.str2term "2 * x \<up> 3 * y \<up> 4 * z \<up> 6 + 7 * y \<up> 8 + 1")
   109 then () else error "is_poly 1 changed";
   110 if not (is_poly (TermC.str2term "2 * (x \<up> 3 * y \<up> 4 * z \<up> 6 + 7) * y \<up> 8 + 1"))
   111 then () else error "is_poly 2 changed";
   112 
   113 "-------- fun term_of_poly ---------------------------------------------------";
   114 "-------- fun term_of_poly ---------------------------------------------------";
   115 "-------- fun term_of_poly ---------------------------------------------------";
   116 val expT = HOLogic.realT
   117 val Free (_, baseT) = (hd o vars o TermC.str2term) "12 * x \<up> 3 * y \<up> 4 * z \<up> 6";
   118 val p = [(1, [0, 0, 0]), (7, [0, 8, 0]), (2, [3, 4, 5])]
   119 val vs = TermC.vars_of (the (parseNEW ctxt "12 * x \<up> 3 * y \<up> 4 * z \<up> 6"))
   120 (*precondition for [(c, es),...]: legth es = length vs*)
   121 ;
   122 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"
   123 then () else error "term_of_poly 1 changed";
   124 
   125 "-------- integration lev.1 fun factout_p_ -----------------------------------";
   126 "-------- integration lev.1 fun factout_p_ -----------------------------------";
   127 "-------- integration lev.1 fun factout_p_ -----------------------------------";
   128 val t = TermC.str2term "(x \<up> 2 + -1*y \<up> 2) / (x \<up> 2 + -1*x*y)"
   129 val SOME (t', asm) = factout_p_ thy t;
   130 if UnparseC.term t' = "(x + y) * (x + -1 * y) / (x * (x + -1 * y))"
   131 then () else error ("factout_p_ term 1 changed: " ^ UnparseC.term t')
   132 ;
   133 if UnparseC.terms asm = "[\"x \<noteq> 0\",\"x + -1 * y \<noteq> 0\"]"
   134 then () else error "factout_p_ asm 1 changed"
   135 ;
   136 val t = TermC.str2term "nothing + to_cancel ::real";
   137 if NONE = factout_p_ thy t then () else error "factout_p_ doesn't report non-applicable";
   138 ;
   139 val t = TermC.str2term "((3 * x \<up> 2 + 6 *x + 3) / (2*x + 2))";
   140 val SOME (t', asm) = factout_p_ thy t;
   141 if UnparseC.term t' = "(3 + 3 * x) * (1 + x) / (2 * (1 + x))" andalso 
   142   UnparseC.terms asm = "[\"1 + x \<noteq> 0\"]"
   143 then () else error "factout_p_ 1 changed";
   144 
   145 "-------- integration lev.1 fun cancel_p_ ------------------------------------";
   146 "-------- integration lev.1 fun cancel_p_ ------------------------------------";
   147 "-------- integration lev.1 fun cancel_p_ ------------------------------------";
   148 val t = TermC.str2term "(x \<up> 2 + -1*y \<up> 2) / (x \<up> 2 + -1*x*y)"
   149 val SOME (t', asm) = cancel_p_ thy t;
   150 if (UnparseC.term t', UnparseC.terms asm) = ("(x + y) / x", "[\"x \<noteq> 0\"]")
   151 then () else error ("cancel_p_ (t', asm) 1 changed: " ^ UnparseC.term t')
   152 ;
   153 val t = TermC.str2term "nothing + to_cancel ::real";
   154 if NONE = cancel_p_ thy t then () else error "cancel_p_ doesn't report non-applicable";
   155 ;
   156 val t = TermC.str2term "((3 * x \<up> 2 + 6 *x + 3) / (2*x + 2))";
   157 val SOME (t', asm) = cancel_p_ thy t;
   158 if UnparseC.term t' = "(3 + 3 * x) / 2" andalso UnparseC.terms asm = "[]"
   159 then () else error "cancel_p_ 1 changed";
   160 
   161 "-------- integration lev.1 fun common_nominator_p_ --------------------------";
   162 "-------- integration lev.1 fun common_nominator_p_ --------------------------";
   163 "-------- integration lev.1 fun common_nominator_p_ --------------------------";
   164 val t = TermC.str2term ("y / (a*x + b*x + c*x) " ^
   165               (* n1    d1                   *)
   166                 "+ a / (x*y)");
   167               (* n2    d2                   *)
   168 val SOME (t', asm) = common_nominator_p_ thy t;
   169 if UnparseC.term t' =
   170       ("y * y / (x * ((a + b + c) * y)) " ^
   171   (*  n1  *d2'/ (c'* ( d1'        *d2')) *)
   172      "+ a * (a + b + c) / (x * ((a + b + c) * y))")
   173    (*  n2 * d1'         / (c'* ( d1'        *d2')) *)
   174 then () else error "common_nominator_p_ term 1 changed";
   175 if UnparseC.terms asm = "[\"a + b + c \<noteq> 0\",\"y \<noteq> 0\",\"x \<noteq> 0\"]"
   176 then () else error "common_nominator_p_ asm 1 changed"
   177 
   178 "-------- example in mail Nipkow";
   179 val t = TermC.str2term "x/(x \<up> 2 + -1*y \<up> 2) + y/(x \<up> 2 + -1*x*y)";
   180 val SOME (t', asm) = common_nominator_p_ thy t;
   181 if UnparseC.term t' = "x * x / " ^ 
   182                  "((x + -1 * y) * ((x + y) * x))" ^
   183             " +\n" ^ 
   184                  "y * (x + y) / " ^ 
   185                  "((x + -1 * y) * ((x + y) * x))"
   186 then () else error "common_nominator_p_ term 2 changed"
   187 ;
   188 if UnparseC.terms asm = "[\"x + y \<noteq> 0\",\"x \<noteq> 0\",\"x + -1 * y \<noteq> 0\"]"
   189 then () else error "common_nominator_p_ asm 2 changed"
   190 
   191 "-------- example: applicable tested by SML code";
   192 val t = TermC.str2term "nothing / to_add";
   193 if NONE = common_nominator_p_ thy t then () else error "common_nominator_p_ term 3 changed";
   194 ;
   195 val t = TermC.str2term "((x + (-1)) / (x + 1)) + ((x + 1) / (x + (-1)))";
   196 val SOME (t', asm) = common_nominator_p_ thy t;
   197 if UnparseC.term t' = 
   198    "(x + -1) * (-1 + x) / ((1 + x) * (-1 + x)) +\n(x + 1) * (1 + x) / ((1 + x) * (-1 + x))"
   199   andalso UnparseC.terms asm = "[\"1 + x \<noteq> 0\",\"-1 + x \<noteq> 0\"]"
   200 then () else error "common_nominator_p_ 3 changed";
   201 
   202 "-------- integration lev.1 fun add_fraction_p_ ------------------------------";
   203 "-------- integration lev.1 fun add_fraction_p_ ------------------------------";
   204 "-------- integration lev.1 fun add_fraction_p_ ------------------------------";
   205 val t = TermC.str2term "((x + (-1)) / (x + 1)) + ((x + 1) / (x + (-1)))";
   206 val SOME (t', asm) = add_fraction_p_ thy t;
   207 if UnparseC.term t' = "(2 + 2 * x \<up> 2) / (-1 + x \<up> 2)" 
   208 then () else error "add_fraction_p_ 3 changed";
   209 ;
   210 if UnparseC.terms asm = "[\"-1 + x \<up> 2 \<noteq> 0\"]"
   211 then () else error "add_fraction_p_ 3 changed";
   212 ;
   213 val t = TermC.str2term "nothing / to_add";
   214 if NONE = add_fraction_p_ thy t then () else error "add_fraction_p_ term 3 changed";
   215 ;
   216 val t = TermC.str2term "((x + (-1)) / (x + 1)) + ((x + 1) / (x + (-1)))";
   217 val SOME (t', asm) = add_fraction_p_ thy t;
   218 if UnparseC.term t' = "(2 + 2 * x \<up> 2) / (-1 + x \<up> 2)" andalso
   219   UnparseC.terms asm = "[\"-1 + x \<up> 2 \<noteq> 0\"]"
   220 then () else error "add_fraction_p_ 3 changed";
   221 
   222 "-------- and app_rev ...traced down from rewrite_set_ until prepats ---------";
   223 "-------- and app_rev ...traced down from rewrite_set_ until prepats ---------";
   224 "-------- and app_rev ...traced down from rewrite_set_ until prepats ---------";
   225 (* trace down until prepats are evaluated 
   226   (which does not to work, because substitution is not done -- compare rew_sub!);
   227   keep this sequence for the case, factout_p, cancel_p, common_nominator_p, add_fraction_p
   228   (again) get prepat = [] changed to <>[]. *)
   229 val t = TermC.str2term "(x \<up> 2 + -1*y \<up> 2) / (x \<up> 2 + -1*x*y)";
   230 
   231 (*rewrite_set_ @{theory Isac_Knowledge} true cancel t = NONE; !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!*)
   232 "~~~~~ fun rewrite_set_, args:"; val (thy, bool, rls, term) = (thy, false, cancel_p, t);
   233 "~~~~~ fun rewrite__set_, args:"; val (thy, i, _, _, (rrls as Rrls _), t) =
   234   (thy, 1, bool, [], rls, term);
   235 (*val (t', asm, rew) = app_rev thy (i+1) rrls t; rew = false!!!!!!!!!!!!!!!!!!!!!*)
   236 "~~~~~ and app_rev, args:"; val (thy, i, rrls, t) = (thy, (i+1), rrls, t);
   237     fun chk_prepat thy erls [] t = true
   238       | chk_prepat thy erls prepat t =
   239         let
   240           fun chk (pres, pat) =
   241             (let 
   242               val subst: Type.tyenv * Envir.tenv =
   243                 Pattern.match thy (pat, t) (Vartab.empty, Vartab.empty)
   244              in
   245               snd (eval__true thy (i + 1) (map (Envir.subst_term subst) pres) [] erls)
   246              end) handle Pattern.MATCH => false
   247            fun scan_ f [] = false (*scan_ NEVER called by []*)
   248              | scan_ f (pp::pps) =
   249                if f pp then true else scan_ f pps;
   250         in scan_ chk prepat end;
   251     (* apply the normal_form of a rev-set *)
   252     fun app_rev' thy (Rrls{erls,prepat,scr=Rfuns{normal_form,...},...}) t =
   253       if chk_prepat thy erls prepat t
   254       then ((*tracing("### app_rev': t = "^UnparseC.term t);*) normal_form t)
   255       else NONE;
   256 (*  val opt = app_rev' thy rrls t  ..NONE!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!*)
   257 "~~~~~ and app_rev', args:"; val (thy, (Rrls{erls,prepat,scr=Rfuns{normal_form,...},...}), t) =
   258   (thy, rrls, t);
   259 (* chk_prepat thy erls prepat t = false!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!*)
   260 (* app_sub thy i rrls t = false!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!*)
   261 "~~~~~ fun chk_prepat, args:"; val (thy, erls, prepat, t) = (thy, erls, prepat, t);
   262           fun chk (pres, pat) =
   263             (let 
   264               val subst: Type.tyenv * Envir.tenv =
   265                 Pattern.match thy (pat, t) (Vartab.empty, Vartab.empty)
   266              in
   267               snd (eval__true thy (i + 1) (map (Envir.subst_term subst) pres) [] erls)
   268              end) handle Pattern.MATCH => false
   269            fun scan_ f [] = false (*scan_ NEVER called by []*)
   270              | scan_ f (pp::pps) =
   271                if f pp then true else scan_ f pps;
   272 
   273 (*========== inhibit exn WN130823: prepat is empty ====================================
   274 (* scan_ chk prepat = false!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!*)
   275 "~~~~~ fun , args:"; val (f, (pp::pps)) = (chk, prepat);
   276 f;
   277 val ([t1, t2], t) = pp;
   278 UnparseC.term t1 = "?r is_expanded";
   279 UnparseC.term t2 = "?s is_expanded";
   280 UnparseC.term t = "?r / ?s";
   281 (* f pp = false!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!*)
   282 "~~~~~ fun chk, args:"; val (pres, pat) = (pp);
   283               val subst: Type.tyenv * Envir.tenv =
   284                 Pattern.match thy (pat, t) (Vartab.empty, Vartab.empty)
   285 (*subst = 
   286   ({}, {(("r", 0), ("real", Var (("r", 0), "real"))), 
   287         (("s", 0), ("real", Var (("s", 0), "real")))}*)
   288 ;
   289               snd (eval__true thy (i + 1) (map (Envir.subst_term subst) pres) [] erls)
   290 "~~~~~ fun eval__true, args:"; val (thy, i, asms, bdv, rls) =
   291   (thy, (i + 1), (map (Envir.subst_term subst) pres), [], erls);
   292 UnparseC.terms asms;                         (* = "[\"?r is_expanded\",\"?s is_expanded\"]"*)
   293 asms = [@{term True}] orelse asms = []; (* = false*)
   294 asms = [@{term False}]                ; (* = false*)
   295 "~~~~~ fun chk, args:"; val (indets, (a::asms)) = ([], asms);
   296 bdv (*= []: _a list*);
   297 val bdv : (term * term) list = [];
   298 rewrite__set_ thy (i+1) false;
   299 UnparseC.term a = "?r is_expanded"; (*hier m"usste doch der Numerator eingesetzt sein ??????????????*)
   300 val SOME (Const ("HOL.False", _), []) = rewrite__set_ thy (i+1) false bdv rls a
   301 ============ inhibit exn WN130823: prepat is empty ===================================*)
   302 
   303 "-------- fun rewrite_set_ cancel_p downto fun gcd_poly ----------------------";
   304 "-------- fun rewrite_set_ cancel_p downto fun gcd_poly ----------------------";
   305 "-------- fun rewrite_set_ cancel_p downto fun gcd_poly ----------------------";
   306 val t = TermC.str2term "(12 * x * y) / (8 * y \<up> 2 )";
   307 (* "-------- example 187a": exception Div raised...
   308 val SOME (t', asm) = rewrite_set_ thy false cancel_p t;*)
   309 val t = TermC.str2term "(8 * x \<up> 2 * y * z ) / (18 * x * y \<up> 2 * z )";
   310 (* "-------- example 187b": doesn't terminate...
   311 val SOME (t', asm) = rewrite_set_ thy false cancel_p t;*)
   312 val t = TermC.str2term "(9 * x \<up> 5 * y \<up> 2 * z \<up> 4) / (15 * x \<up> 6 * y \<up> 3 * z )";
   313 (* "-------- example 187c": doesn't terminate...
   314 val SOME (t', asm) = rewrite_set_ thy false cancel_p t;*)
   315 "~~~~~ fun rewrite_set_, args:"; val (thy, bool, rls, term) = (@{theory Isac_Knowledge}, false, cancel_p, t);
   316 (* WN130827: exception Div raised...
   317 rewrite__set_ thy 1 bool [] rls term
   318 *)
   319 "~~~~~ and rewrite__set_, args:"; val (thy, i, _, _, (rrls as Rrls _), t) =
   320   (thy, 1, bool, [], rls, term);
   321 (* WN130827: exception Div raised...
   322 	val (t', asm, rew) = app_rev thy (i+1) rrls t
   323 *)
   324 "~~~~~ fun app_rev, args:"; val (thy, i, rrls, t) = (thy, (i+1), rrls, t);
   325 (* WN130827: exception Div raised...
   326     val opt = app_rev' thy rrls t
   327 *)
   328 "~~~~~ fun app_rev', args:"; val (thy, (Rrls{erls,prepat,scr=Rfuns{normal_form,...},...}), t) =
   329   (thy, rrls, t);
   330 chk_prepat thy erls prepat t    = true;
   331 (* WN130827: exception Div raised...
   332 normal_form t
   333 *)
   334 (* lookup Rational.thy, cancel_p: normal_form = cancel_p_ thy*)
   335 "~~~~~ fun cancel_p_, args:"; val (t) = (t);
   336 val opt = check_fraction t;
   337 val SOME (numerator, denominator) = opt
   338         val vs = TermC.vars_of t
   339         val baseT = type_of numerator
   340         val expT = HOLogic.realT
   341 val (SOME a, SOME b) = (poly_of_term vs numerator, poly_of_term vs denominator);
   342 (*"-------- example 187a": exception Div raised...
   343 val a = [(12, [1, 1])]: poly
   344 val b = [(8, [0, 2])]: poly
   345               val ((a', b'), c) = gcd_poly a b
   346 *)
   347 (* "-------- example 187b": doesn't terminate...
   348 val a = [(8, [2, 1, 1])]: poly
   349 val b = [(18, [1, 2, 1])]: poly
   350               val ((a', b'), c) = gcd_poly a b
   351 *)
   352 (* "-------- example 187c": doesn't terminate...
   353 val a = [(9, [5, 2, 4])]: poly
   354 val b = [(15, [6, 3, 1])]: poly
   355               val ((a', b'), c) = gcd_poly a b
   356 *)
   357 
   358 "-------- rls norm_Rational downto fun gcd_poly ------------------------------";
   359 "-------- rls norm_Rational downto fun gcd_poly ------------------------------";
   360 "-------- rls norm_Rational downto fun gcd_poly ------------------------------";
   361 val t = TermC.str2term "(x \<up> 2 - 4)*(3 - y) / ((y \<up> 2 - 9)*(2+x))";
   362 Rewrite.trace_on := false (*true false*);
   363 (* trace stops with ...: (and then jEdit hangs)..
   364 rewrite_set_ thy false norm_Rational t;
   365 :
   366 ###  rls: cancel_p on: (-12 + 4 * y + 3 * x \<up> 2 + -1 * (x \<up> 2 * y)) /
   367 (-18 + -9 * x + 2 * y \<up> 2 + x * y \<up> 2)
   368 *)
   369 val t = TermC.str2term (*copy from above: "::real" is not required due to " \<up> "*)
   370   ("(-12 + 4 * y + 3 * x \<up> 2 + -1 * (x \<up> 2 * y)) /" ^
   371   "(-18 + -9 * x + 2 * y \<up> 2 + x * y \<up> 2)");
   372 (*cancel_p_ thy t;
   373 exception Div raised*)
   374 
   375 "~~~~~ fun cancel_p_, args:"; val (t) = (t);
   376 val opt = check_fraction t;
   377 val SOME (numerator, denominator) = opt
   378         val vs = TermC.vars_of t
   379         val baseT = type_of numerator
   380         val expT = HOLogic.realT;
   381 (*default_print_depth 3; 999*)
   382 val (SOME a, SOME b) = (poly_of_term vs numerator, poly_of_term vs denominator);
   383 (*default_print_depth 3; 999*)
   384 (* does not terminate instead of returning ?:
   385         val ((a', b'), c) = gcd_poly a b
   386 val a = [(~12, [0, 0]), (3, [2, 0]), (4, [0, 1]), (~1, [2, 1])]: poly
   387 val b = [(~18, [0, 0]), (~9, [1, 0]), (2, [0, 2]), (1, [1, 2])]: poly
   388 *)
   389 
   390 "-------- rls norm_Rational downto fun add_fraction_p_ -----------------------";
   391 "-------- rls norm_Rational downto fun add_fraction_p_ -----------------------";
   392 "-------- rls norm_Rational downto fun add_fraction_p_ -----------------------";
   393 val thy =  @{theory Isac_Knowledge};
   394 "----- SK060904-2a non-termination of add_fraction_p_";
   395 val t = TermC.str2term (" (a + b * x) / (a + -1 * (b * x)) +  " ^
   396 		         " (-1 * a + b * x) / (a + b * x)      ");
   397 (* rewrite_set_ thy false norm_Rational t
   398 exception Div raised*)
   399 (* rewrite_set_ thy false add_fractions_p t;
   400 exception Div raised*)
   401 "~~~~~ fun rewrite_set_, args:"; val (thy, bool, rls, term) =
   402   (@{theory Isac_Knowledge}, false, add_fractions_p, t);
   403 "~~~~~ and rewrite__set_, args:"; val (thy, i, _, _, (rrls as Rrls _), t) =
   404   (thy, 1, bool, [], rls, term);
   405 (* app_rev thy (i+1) rrls t;
   406 exception Div raised*)
   407 "~~~~~ and app_rev, args:"; val (thy, i, rrls, t) = (thy, (i+1), rrls, t);
   408     fun chk_prepat thy erls [] t = true
   409       | chk_prepat thy erls prepat t =
   410         let
   411           fun chk (pres, pat) =
   412             (let 
   413               val subst: Type.tyenv * Envir.tenv =
   414                 Pattern.match thy (pat, t) (Vartab.empty, Vartab.empty)
   415              in
   416               snd (eval__true thy (i + 1) (map (Envir.subst_term subst) pres) [] erls)
   417              end) handle Pattern.MATCH => false
   418            fun scan_ f [] = false (*scan_ NEVER called by []*)
   419              | scan_ f (pp::pps) =
   420                if f pp then true else scan_ f pps;
   421         in scan_ chk prepat end;
   422     (* apply the normal_form of a rev-set *)
   423     fun app_rev' thy (Rrls{erls,prepat,scr=Rfuns{normal_form,...},...}) t =
   424       if chk_prepat thy erls prepat t
   425       then ((*tracing("### app_rev': t = "^UnparseC.term t);*) normal_form t)
   426       else NONE;
   427 (*  val opt = app_rev' thy rrls t;
   428 exception Div raised*)
   429 (*  val opt = app_rev' thy rrls t;
   430 exception Div raised*)
   431 "~~~~~ and app_rev', args:"; val (thy, (Rrls{erls,prepat,scr=Rfuns{normal_form,...},...}), t) =
   432   (thy, rrls, t);
   433 chk_prepat thy erls prepat t = true       = true;
   434 (*normal_form t
   435 exception Div raised*)
   436 (* lookup Rational.thy, val add_fractions_p: normal_form = add_fraction_p_ thy*)
   437 (*add_fraction_p_ thy t
   438 exception Div raised*)
   439 "~~~~~ fun add_fraction_p_, args:"; val ((_: theory), t) = (thy, t);
   440 val SOME ((n1, d1), (n2, d2)) = check_frac_sum t;
   441 UnparseC.term n1; UnparseC.term d1; UnparseC.term n2; UnparseC.term d2;
   442       val vs = TermC.vars_of t;
   443 (*default_print_depth 3; 999*)
   444 val (SOME _, SOME a, SOME _, SOME b) =
   445   (poly_of_term vs n1, poly_of_term vs d1, poly_of_term vs n2, poly_of_term vs d2);
   446 (*default_print_depth 3; 999*)
   447 (*
   448 val a = [(1, [1, 0, 0]), (~1, [0, 1, 1])]: poly
   449 val b = [(1, [1, 0, 0]), (1, [0, 1, 1])]: poly
   450             val ((a', b'), c) = gcd_poly a b
   451 *)
   452 
   453 "----------- fun check_frac_sum with Free A and Const AA ---------------------------------------";
   454 "----------- fun check_frac_sum with Free A and Const AA ---------------------------------------";
   455 "----------- fun check_frac_sum with Free A and Const AA ---------------------------------------";
   456 val thy = @{theory Isac_Knowledge(*Partial_Fractions*)}
   457 val ctxt = Proof_Context.init_global thy;
   458 
   459 (*---------- (1) with Free A, B  ----------------------------------------------------------------*)
   460 val t = (the o (parseNEW  ctxt)) "3 = A / 2 + A / 4 + (B / 2 + -1 * B / (2::real))";
   461                                 (* required for applying thms in rewriting  \<up> ^*)
   462 (* we get details from here..*)
   463 
   464 Rewrite.trace_on := false;
   465 val SOME (t', _) = Rewrite.rewrite_set_ thy true add_fractions_p t;
   466 Rewrite.trace_on := false;
   467 (* Rewrite.trace_on:
   468 add_fractions_p on: 3 = A / 2 + A / 4 + (B / 2 + -1 * B / 2) --> 3 = A / 2 + A / 4 + 0 / 2 *)
   469                      (* |||||||||||||||||||||||||||||||||||| *)
   470 
   471 val t = (the o (parseNEW  ctxt))(* ||||||||||||||||||||||||| GUESS 1 GUESS 1 GUESS 1 GUESS 1 *)
   472                        "A / 2 + A / 4 + (B / 2 + -1 * B / (2::real))";
   473 "~~~~~ fun add_fraction_p_ , ad-hoc args:"; val (t) = (t);
   474 val NONE = (*case*) check_frac_sum t (*of*)
   475 
   476 (* Rewrite.trace_on:
   477 add_fractions_p on: 3 = A / 2 + A / 4 + (B / 2 + -1 * B / 2) --> 3 = A / 2 + A / 4 + 0 / 2 *)
   478                      (*         |||||||||||||||||||||||||||| *)
   479 val t = (the o (parseNEW  ctxt))(* ||||||||||||||||||||||||| GUESS 2 GUESS 2 GUESS 2 GUESS 2 *)
   480                                "A / 4 + (B / 2 + -1 * B / (2::real))";
   481 "~~~~~ fun add_fraction_p_ , ad-hoc args:"; val (t) = (t);
   482 val SOME ((n1, d1), (n2, d2)) = (*case*) check_frac_sum t (*of*);
   483 (*+*)if (UnparseC.term n1, UnparseC.term d1) = ("A"                 , "4") andalso
   484 (*+*)   (UnparseC.term n2, UnparseC.term d2) = ("B / 2 + -1 * B / 2", "1")
   485 (*+*)then () else error "check_frac_sum (A / 4 + (B / 2 + -1 * B / (2::real))) changed";
   486 
   487       val vs = TermC.vars_of t;
   488 val (SOME [(1, [1, 0])], SOME [(4, [0, 0])], NONE, SOME [(1, [0, 0])]) =
   489   (*case*) (poly_of_term vs n1, poly_of_term vs d1, poly_of_term vs n2, poly_of_term vs d2) (*of*);
   490 
   491 "~~~~~ fun poly_of_term , args:"; val (vs, t) = (vs, n1);
   492 val SOME [(1, [xxx, 0])] = SOME [monom_of_term vs (1, replicate (length vs) 0) t];
   493 (*+*)if xxx = 1 then () else error "monom_of_term changed"
   494 
   495 "~~~~~ fun monom_of_term , args:"; val (vs, (c, es), (Free (id, _))) =
   496   (vs, (1, replicate (length vs) 0), t);
   497 case vs of [Free ("A", _), Free ("B", _)] =>
   498   if c = 1 andalso id = "A"
   499   then () else error "monom_of_term Free changed 1"
   500 | _ => error "monom_of_term Free changed 2";
   501 
   502 (*---------- (2) with Const AA, BB --------------------------------------------------------------*)
   503 val t = (the o (parseNEW  ctxt)) "3 = AA / 2 + AA / 4 + (BB / 2 + -1 * BB / 2)";
   504                                     (*AA :: real*)
   505 (* we get details from here..*)
   506 
   507 Rewrite.trace_on := false;
   508 val SOME (t', _) = Rewrite.rewrite_set_ thy true add_fractions_p t;
   509 Rewrite.trace_on := false;
   510 (* Rewrite.trace_on:
   511 add_fractions_p on: 3 = A / 2 + A / 4 + (B / 2 + -1 * B / 2) --> 3 = A / 2 + A / 4 + 0 / 2 *)
   512                      (* |||||||||||||||||||||||||||||||||||| *)
   513 val t = (the o (parseNEW  ctxt))(* ||||||||||||||||||||||||| *)
   514                    "AA / 2 + AA / 4 + (BB / 2 + -1 * BB / 2)";
   515 "~~~~~ fun add_fraction_p_ , ad-hoc args:"; val (t) = (t);
   516 val NONE = (*case*) check_frac_sum t (*of*)
   517 
   518 (* Rewrite.trace_on:
   519 add_fractions_p on: 3 = A / 2 + A / 4 + (B / 2 + -1 * B / 2) --> 3 = A / 2 + A / 4 + 0 / 2 *)
   520                      (*         |||||||||||||||||||||||||||| *)
   521 val t = (the o (parseNEW  ctxt))(* ||||||||||||||||||||||||| *)
   522                                "AA / 4 + (BB / 2 + -1 * BB / 2)";
   523 "~~~~~ fun add_fraction_p_ , ad-hoc args:"; val (t) = (t);
   524 val SOME ((n1, d1), (n2, d2)) = (*case*) check_frac_sum t (*of*);
   525 (*+*)if (UnparseC.term n1, UnparseC.term d1) = ("AA"                 , "4") andalso
   526 (*+*)   (UnparseC.term n2, UnparseC.term d2) = ("BB / 2 + -1 * BB / 2", "1")
   527 (*+*)then () else error "check_frac_sum (AA / 4 + (BB / 2 + -1 * BB / 2)) changed";
   528 
   529       val vs = TermC.vars_of t;
   530 val (SOME [(1, [1, 0])], SOME [(4, [0, 0])], NONE, SOME [(1, [0, 0])]) =
   531   (*case*) (poly_of_term vs n1, poly_of_term vs d1, poly_of_term vs n2, poly_of_term vs d2) (*of*);
   532 
   533 "~~~~~ fun poly_of_term , args:"; val (vs, t) = (vs, n1);
   534 val SOME [(1, [xxx, 0])] = SOME [monom_of_term vs (1, replicate (length vs) 0) t];
   535 (*+*)if xxx = 1 then () else error "monom_of_term changed"
   536 
   537 "~~~~~ fun monom_of_term , args:"; val (vs, (c, es), (Const (id, _))) =
   538   (vs, (1, replicate (length vs) 0), t);
   539 case vs of [Const ("Partial_Fractions.AA", _), Const ("Partial_Fractions.BB", _)] =>
   540   if c = 1 andalso id = "Partial_Fractions.AA"
   541   then () else error "monom_of_term Const changed 1"
   542 | _ => error "monom_of_term Const changed 2";
   543 
   544 "----------- fun cancel_p with Const AA --------------------------------------------------------";
   545 "----------- fun cancel_p with Const AA --------------------------------------------------------";
   546 "----------- fun cancel_p with Const AA --------------------------------------------------------";
   547 val thy = @{theory Partial_Fractions};
   548 val ctxt = Proof_Context.init_global @{theory}
   549 val SOME t = TermC.parseNEW ctxt "2 * AA / 2"; (* Const ("Free ("AA", "real") *)
   550 
   551 val SOME (t', _) = rewrite_set_ thy true cancel_p t;
   552 case t' of
   553   Const ("Rings.divide_class.divide", _) $ Const ("Partial_Fractions.AA", _) $ Free ("1", _) => ()
   554 | _ => error "WRONG rewrite_set_ cancel_p (2 * AA / 2) \<longrightarrow> AA changed";
   555 
   556 "~~~~~ fun cancel_p , args:"; val (t) = (t);
   557 val opt = check_fraction t
   558 val SOME (numerator, denominator) = (*case*) opt (*of*);
   559 
   560 if UnparseC.term numerator = "2 * AA" andalso UnparseC.term denominator = "2"
   561 then () else error "check_fraction (2 * AA / 2) changed";
   562         val vs = TermC.vars_of t;
   563 case vs of
   564   [Const ("Partial_Fractions.AA", _)] => ()
   565 | _ => error "rewrite_set_ cancel_p (2 * AA / 2) \<longrightarrow> AA/1  changed";
   566 
   567 
   568 "-------- rewrite_set_ cancel_p from: Mathematik 1 Schalk Reniets Verlag -----";
   569 "-------- rewrite_set_ cancel_p from: Mathematik 1 Schalk Reniets Verlag -----";
   570 "-------- rewrite_set_ cancel_p from: Mathematik 1 Schalk Reniets Verlag -----";
   571 val thy  = @{theory "Rational"};
   572 "-------- WN";
   573 val t = TermC.str2term "(2 + -3 * x) / 9";
   574 if NONE = rewrite_set_ thy false cancel_p t then ()
   575 else error "rewrite_set_ cancel_p must return NONE, if the term cannot be cancelled";
   576 
   577 "-------- example 186a";
   578 val t = TermC.str2term "(14 * x * y) / (x * y)";
   579   is_expanded (TermC.str2term "14 * x * y");
   580   is_expanded (TermC.str2term "x * y");
   581 val SOME (t', asm) = rewrite_set_ thy false cancel_p t;
   582 if (UnparseC.term t', UnparseC.terms asm) = ("14 / 1", "[]")
   583 then () else error "rational.sml cancel Schalk 186a";
   584 
   585 "-------- example 186b";
   586 val t = TermC.str2term "(60 * a * b) / ( 15 * a  * b )";
   587 val SOME (t', asm) = rewrite_set_ thy false cancel_p t;
   588 if (UnparseC.term t', UnparseC.terms asm) = ("4 / 1", "[]")
   589 then () else error "rational.sml cancel Schalk 186b";
   590 
   591 "-------- example 186c";
   592 val t = TermC.str2term "(144 * a \<up> 2 * b * c) / (12 * a * b * c)";
   593 val SOME (t', asm) = rewrite_set_ thy false cancel_p t;
   594 if (UnparseC.term t', UnparseC.terms asm) = ("12 * a / 1", "[]")
   595 then () else error "rational.sml cancel Schalk 186c";
   596 
   597 (* !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! exception Div raised !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
   598   see --- fun rewrite_set_ downto fun gcd_poly ---
   599 "-------- example 187a";
   600 val t = TermC.str2term "(12 * x * y) / (8 * y \<up> 2 )";
   601 val SOME (t', asm) = rewrite_set_ thy false cancel_p t;
   602 if (UnparseC.term t', UnparseC.terms asm) = ("3 * x / (2 * y)", "[\"4 * y ~= 0\"]")
   603 then () else error "rational.sml cancel Schalk 187a";
   604 *)
   605 
   606 (* doesn't terminate !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
   607   see --- fun rewrite_set_ downto fun gcd_poly ---
   608 "-------- example 187b";
   609 val t = TermC.str2term "(8 * x \<up> 2 * y * z ) / (18 * x * y \<up> 2 * z )";
   610 val SOME (t', asm) = rewrite_set_ thy false cancel_p t;
   611 if (UnparseC.term t', UnparseC.terms asm) = ("4 * x / (9 * y)", "[\"2 * (z * (y * x)) ~= 0\"]")
   612 then () else error "rational.sml cancel Schalk 187b";
   613 *)
   614 
   615 (* doesn't terminate !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
   616   see --- fun rewrite_set_ downto fun gcd_poly ---
   617 "-------- example 187c";
   618 val t = TermC.str2term "(9 * x \<up> 5 * y \<up> 2 * z \<up> 4) / (15 * x \<up> 6 * y \<up> 3 * z )";
   619 val SOME (t', asm) = rewrite_set_ thy false cancel_p t;
   620 if (UnparseC.term t', UnparseC.terms asm) = 
   621   ("3 * z \<up> 3 / (5 * (y * x))", "[\"3 * (z * (y \<up> 2 * x \<up> 5)) ~= 0\"]") 
   622 then () else error "rational.sml cancel Schalk 187c";
   623 *)
   624 
   625 "-------- example 188a";
   626 val t = TermC.str2term "(-8 + 8 * x) / (-9 + 9 * x)";
   627   is_expanded (TermC.str2term "8 * x + -8");
   628 val SOME (t', asm) = rewrite_set_ thy false cancel_p t;
   629 if (UnparseC.term t', UnparseC.terms asm) = ("8 / 9", "[]")
   630 then () else error "rational.sml cancel Schalk 188a";
   631 
   632 val t = TermC.str2term "(8*((-1) + x))/(9*((-1) + x))";
   633 val SOME (t, _) = rewrite_set_ thy false make_polynomial t;
   634 if (UnparseC.term t', UnparseC.terms asm) = ("8 / 9", "[]")
   635 then () else error "rational.sml cancel Schalk make_polynomial 1";
   636 
   637 "-------- example 188b";
   638 val t = TermC.str2term "(-15 + 5 * x) / (-18 + 6 * x)";
   639 val SOME (t', asm) = rewrite_set_ thy false cancel_p t;
   640 if (UnparseC.term t', UnparseC.terms asm) = ("5 / 6", "[]")
   641 then () else error "rational.sml cancel Schalk 188b";
   642 
   643 "-------- example 188c";
   644 val t = TermC.str2term "(a + -1 * b) / (b + -1 * a)";
   645 val SOME (t', asm) = rewrite_set_ thy false  cancel_p t;
   646 if (UnparseC.term t', UnparseC.terms asm) = ("-1 / 1", "[]")
   647 then () else error "rational.sml cancel Schalk 188c";
   648 
   649 is_expanded (TermC.str2term "a + -1 * b") = true;
   650 val t = TermC.str2term "((-1)*(b + (-1) * a))/(1*(b + (-1) * a))";
   651 val SOME (t', asm) = rewrite_set_ thy false make_polynomial t;
   652 if (UnparseC.term t', UnparseC.terms asm) = ("(a + -1 * b) / (-1 * a + b)", "[]")
   653 then () else error "rational.sml cancel Schalk make_polynomial 2";
   654 
   655 "-------- example 190a";
   656 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 )";
   657 val SOME (t', asm) = rewrite_set_ thy false cancel_p t;
   658 if (UnparseC.term t', UnparseC.terms asm) = 
   659   ("(1 + 9 * a \<up> 2) / (3 * a + 9 * a \<up> 2)", "[\"3 * a + 9 * a \<up> 2 \<noteq> 0\"]")
   660 then () else error "rational.sml cancel Schalk 190a";
   661 
   662 "-------- example 190c";
   663 val t = TermC.str2term "((1 + 9 * a \<up> 2)*(1 + 3 * a))/((3 * a + 9 * a \<up> 2)*(1 + 3 * a))";
   664 val SOME (t', asm) = rewrite_set_ thy false make_polynomial t;
   665 if (UnparseC.term t', UnparseC.terms asm) = 
   666   ("(1 + 3 * a + 9 * a \<up> 2 + 27 * a \<up> 3) /\n(3 * a + 18 * a \<up> 2 + 27 * a \<up> 3)", "[]")
   667 then () else error "rational.sml make_polynomial Schalk 190c";
   668 
   669 "-------- example 191a";
   670 val t = TermC.str2term "( x \<up> 2 + -1 * y \<up> 2 ) / ( x + y )";
   671   is_expanded (TermC.str2term "x \<up> 2 + -1 * y \<up> 2") = false; (*!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!*)
   672   is_expanded (TermC.str2term "x + y") = true;
   673 val SOME (t', asm) = rewrite_set_ thy false cancel_p t;
   674 if (UnparseC.term t', UnparseC.terms asm) = ("(x + -1 * y) / 1", "[]")
   675 then () else error "rational.sml make_polynomial Schalk 191a";
   676 
   677 "-------- example 191b";
   678 val t = TermC.str2term "((x + (-1) * y)*(x + y))/((1)*(x + y))";
   679 val SOME (t', asm) = rewrite_set_ thy false make_polynomial t;
   680 if (UnparseC.term t', UnparseC.terms asm) = ("(x \<up> 2 + -1 * y \<up> 2) / (x + y)", "[]")
   681 then () else error "rational.sml make_polynomial Schalk 191b";
   682 
   683 "-------- example 191c";
   684 val t = TermC.str2term "( 9 * x \<up> 2 + -30 * x + 25 ) / ( 9 * x \<up> 2 + -25 )";
   685   is_expanded (TermC.str2term "9 * x \<up> 2 + -30 * x + 25") = true;
   686   is_expanded (TermC.str2term "25 + -30*x + 9*x \<up> 2") = true;
   687   is_expanded (TermC.str2term "-25 + 9*x \<up> 2") = true;
   688 
   689 val t = TermC.str2term "(((-5) + 3 * x)*((-5) + 3 * x))/((5 + 3 * x)*((-5) + 3 * x))";
   690 val SOME (t', asm) = rewrite_set_ thy false make_polynomial t;
   691 if (UnparseC.term t', UnparseC.terms asm) = ("(25 + -30 * x + 9 * x \<up> 2) / (-25 + 9 * x \<up> 2)", "[]")
   692 then () else error "rational.sml make_polynomial Schalk 191c";
   693 
   694 "-------- example 192b";
   695 val t = TermC.str2term "( 7 * x \<up> 3 + -1 * x \<up> 2 * y ) / ( 7 * x * y \<up> 2 + -1 *  y \<up> 3 )";
   696 val SOME (t', asm) = rewrite_set_ thy false cancel_p t;
   697 if (UnparseC.term t', UnparseC.terms asm) = ("x \<up> 2 / y \<up> 2", "[\"y \<up> 2 \<noteq> 0\"]")
   698 then () else error "rational.sml cancel_p Schalk 192b";
   699 
   700 val t = TermC.str2term "((x \<up> 2)*(7 * x + (-1) * y))/((y \<up> 2)*(7 * x + (-1) * y))";
   701 val SOME (t', asm) = rewrite_set_ thy false make_polynomial t;
   702 if (UnparseC.term t', UnparseC.terms asm) = 
   703   ("(7 * x \<up> 3 + -1 * x \<up> 2 * y) / (7 * x * y \<up> 2 + -1 * y \<up> 3)", "[]")
   704 then () else error "rational.sml make_polynomial Schalk 192b";
   705 
   706 val t = TermC.str2term "((x \<up> 2)*(7 * x + (-1) * y))/((y \<up> 2)*(7 * x + (-1) * y))";
   707 val SOME (t', asm) = rewrite_set_ thy false make_polynomial t;
   708 if (UnparseC.term t', UnparseC.terms asm) = 
   709   ("(7 * x \<up> 3 + -1 * x \<up> 2 * y) / (7 * x * y \<up> 2 + -1 * y \<up> 3)", "[]")
   710 then () else error "rational.sml make_polynomial Schalk WN050929 not working";
   711 
   712 "-------- example 193a";
   713 val t = TermC.str2term "( x \<up> 2 + -6 * x + 9 ) / ( x \<up> 2 + -9 )";
   714 val SOME (t', asm) = rewrite_set_ thy false cancel_p t;
   715 if (UnparseC.term t', UnparseC.terms asm) = ("(-3 + x) / (3 + x)", "[\"3 + x \<noteq> 0\"]")
   716 then () else error "rational.sml cancel_p Schalk 193a";
   717 
   718 "-------- example 193b";
   719 val t = TermC.str2term "( x \<up> 2 + -8 * x + 16 ) / ( 2 * x \<up> 2 + -32 )";
   720 val SOME (t', asm) = rewrite_set_ thy false cancel_p t;
   721 if (UnparseC.term t', UnparseC.terms asm) = ("(-4 + x) / (8 + 2 * x)", "[\"8 + 2 * x \<noteq> 0\"]")
   722 then () else error "rational.sml cancel_p Schalk 193b";
   723 
   724 "-------- example 193c";
   725 val t = TermC.str2term "( 2 * x + -50 * x \<up> 3 ) / ( 25 * x \<up> 2 + -10 * x + 1 )";
   726 val SOME (t', asm) = rewrite_set_ thy false cancel_p t;
   727 if (UnparseC.term t', UnparseC.terms asm) = 
   728   ("(2 * x + 10 * x \<up> 2) / (1 + -5 * x)", "[\"1 + -5 * x \<noteq> 0\"]")
   729 then () else error "rational.sml cancel_p Schalk 193c";
   730 
   731 (*WN:*)
   732 val t = TermC.str2term "(-25 + 9*x \<up> 2)/(5 + 3*x)";
   733 val SOME (t, asm) = rewrite_set_ thy false cancel_p t;
   734 if (UnparseC.term t', UnparseC.terms asm) = ("(2 * x + 10 * x \<up> 2) / (1 + -5 * x)", "[]")
   735 then () else error "rational.sml cancel WN 1";
   736 
   737 "-------- example heuberger";
   738 val t = TermC.str2term ("(x \<up> 4 + x * y + x \<up> 3 * y + y \<up> 2) / " ^
   739   "(x + 5 * x \<up> 2 + y + 5 * x * y + x \<up> 2 * y \<up> 3 + x * y \<up> 4)");
   740 val SOME (t', asm) = rewrite_set_ thy false cancel_p t;
   741 if (UnparseC.term t', UnparseC.terms asm) = 
   742   ("(x \<up> 3 + y) / (1 + 5 * x + x * y \<up> 3)", "[\"1 + 5 * x + x * y \<up> 3 \<noteq> 0\"]")
   743 then () else error "rational.sml cancel_p heuberger";
   744 
   745 "-------- rewrite_set_ add_fractions_p from: Mathematik 1 Schalk -------------";
   746 "-------- rewrite_set_ add_fractions_p from: Mathematik 1 Schalk -------------";
   747 "-------- rewrite_set_ add_fractions_p from: Mathematik 1 Schalk -------------";
   748 (*deleted example 204 ... 236b at update Isabelle2012-->2013*)
   749 
   750 "-------- integration lev.1 -- lev.5: cancel_p_ & add_fractions_p_ -----------";
   751 "-------- integration lev.1 -- lev.5: cancel_p_ & add_fractions_p_ -----------";
   752 "-------- integration lev.1 -- lev.5: cancel_p_ & add_fractions_p_ -----------";
   753 val t = TermC.str2term ("123 = (a*x)/(b*x) + (c*x)/(d*x) + (e*x)/(f*x::real)");
   754 "-------- gcd_poly integration level 1: works on exact term";
   755 if NONE = cancel_p_ thy t then () else error "cancel_p_ works on exact fraction";
   756 if NONE = add_fraction_p_ thy t then () else error "add_fraction_p_ works on exact fraction";
   757 
   758 "-------- gcd_poly integration level 2: picks out ONE appropriate subterm";
   759 val SOME (t', asm) = rewrite_set_ thy false cancel_p t;
   760 if UnparseC.term t' = "123 = a * x / (b * x) + c * x / (d * x) + e / f" 
   761 then () else error "level 2, rewrite_set_ cancel_p: changed";
   762 val SOME (t', asm) = rewrite_set_ thy false add_fractions_p t;
   763 if UnparseC.term t' = "123 = (b * c * x + a * d * x) / (b * d * x) + e * x / (f * x)"
   764 then () else error "level 2, rewrite_set_ add_fractions_p: changed";
   765 
   766 "-------- gcd_poly integration level 3: rewrites all appropriate subterms";
   767 val SOME (t', asm) = rewrite_set_ thy false cancel_p_rls t;
   768 if UnparseC.term t' = "123 = a / b + c / d + e / f"
   769 then () else error "level 3, rewrite_set_ cancel_p_rls: changed";
   770 val SOME (t', asm) = rewrite_set_ thy false add_fractions_p_rls t; (*CREATE add_fractions_p_rls*)
   771 if UnparseC.term t' = "123 = (b * d * e * x + b * c * f * x + a * d * f * x) / (b * d * f * x)"
   772 then () else error "level 3, rewrite_set_ add_fractions_p_rls: changed";
   773 
   774 "-------- gcd_poly integration level 4: iteration cancel_p -- add_fraction_p";
   775 (* simpler variant *)
   776 val testrls = Rule_Set.append_rules "testrls" Rule_Set.empty [Rls_ cancel_p, Rls_ add_fractions_p]
   777 val SOME (t', asm) = rewrite_set_ thy false testrls t;
   778 (*Rewrite.trace_on := false;
   779 #  rls: testrls on: 123 = a * x / (b * x) + c * x / (d * x) + e * x / (f * x) 
   780 ##  rls: cancel_p on: 123 = a * x / (b * x) + c * x / (d * x) + e * x / (f * x) 
   781 ##  rls: add_fractions_p on: 123 = a * x / (b * x) + c * x / (d * x) + e / f 
   782 ##  rls: cancel_p on: 123 = (b * c * x + a * d * x) / (b * d * x) + e / f 
   783 ##  rls: add_fractions_p on: 123 = (b * c + a * d) / (b * d) + e / f 
   784 ##  rls: cancel_p on: 123 = (b * d * e + b * c * f + a * d * f) / (b * d * f) 
   785 ##  rls: add_fractions_p on: 123 = (b * d * e + b * c * f + a * d * f) / (b * d * f) *)
   786 if UnparseC.term t' = "123 = (b * d * e + b * c * f + a * d * f) / (b * d * f)"
   787 then () else error "level 4, rewrite_set_ *_p: changed";
   788 
   789 (* complicated variant *)
   790 val testrls_rls = Rule_Set.append_rules "testrls_rls" Rule_Set.empty [Rls_ cancel_p_rls, Rls_ add_fractions_p_rls];
   791 val SOME (t', asm) = rewrite_set_ thy false testrls_rls t;
   792 (*#  rls: testrls_rls on: 123 = a * x / (b * x) + c * x / (d * x) + e * x / (f * x) 
   793 ##  rls: cancel_p_rls on: 123 = a * x / (b * x) + c * x / (d * x) + e * x / (f * x) 
   794 ###  rls: cancel_p on: 123 = a * x / (b * x) + c * x / (d * x) + e * x / (f * x) 
   795 ###  rls: cancel_p on: 123 = a * x / (b * x) + c * x / (d * x) + e / f 
   796 ###  rls: cancel_p on: 123 = a * x / (b * x) + c / d + e / f 
   797 ###  rls: cancel_p on: 123 = a / b + c / d + e / f 
   798 ##  rls: add_fractions_p_rls on: 123 = a / b + c / d + e / f 
   799 ###  rls: add_fractions_p on: 123 = a / b + c / d + e / f 
   800 ###  rls: add_fractions_p on: 123 = (b * c + a * d) / (b * d) + e / f 
   801 ###  rls: add_fractions_p on: 123 = (b * d * e + b * c * f + a * d * f) / (b * d * f) 
   802 ##  rls: cancel_p_rls on: 123 = (b * d * e + b * c * f + a * d * f) / (b * d * f) 
   803 ###  rls: cancel_p on: 123 = (b * d * e + b * c * f + a * d * f) / (b * d * f) 
   804 ##  rls: add_fractions_p_rls on: 123 = (b * d * e + b * c * f + a * d * f) / (b * d * f) 
   805 ###  rls: add_fractions_p on: 123 = (b * d * e + b * c * f + a * d * f) / (b * d * f) *)
   806 if UnparseC.term t' = "123 = (b * d * e + b * c * f + a * d * f) / (b * d * f)"
   807 then () else error "level 4, rewrite_set_ *_p_rls: changed"
   808 
   809 "-------- gcd_poly integration level 5: cancel_p & add_fraction_p within norm_Rational";
   810 val SOME (t', asm) = rewrite_set_ thy false norm_Rational t;
   811 if UnparseC.term t' = "123 = (a * d * f + b * c * f + b * d * e) / (b * d * f)"
   812 then () else error "level 5, rewrite_set_ norm_Rational: changed"
   813 
   814 "-------- reverse rewrite ----------------------------------------------------";
   815 "-------- reverse rewrite ----------------------------------------------------";
   816 "-------- reverse rewrite ----------------------------------------------------";
   817 (** the term for which reverse rewriting is demonstrated **)
   818 val t = TermC.str2term "(9 + -1 * x \<up> 2) / (9 + 6 * x + x \<up> 2)";
   819 val Rrls {scr = Rfuns {init_state = ini, locate_rule = loc,
   820   next_rule = nex, normal_form = nor, ...},...} = cancel_p;
   821 
   822 (** normal_form produces the result in ONE step **)
   823   val SOME (t',_) = nor t;
   824 if UnparseC.term t' = "(3 + -1 * x) / (3 + x)" then ()
   825 else error "rational.sml normal_form (9 - x \<up> 2) / (9 - 6 * x + x \<up> 2)";
   826 
   827 (** initialize the interpreter state used by the 'me' **)
   828   val (t, _, revsets, _) = ini t;
   829 
   830 if length (hd revsets) = 11 then () else error "length of revset changed";
   831 if (revsets |> nth 1 |> nth 1 |> id_of_thm) = 
   832   (@{thm realpow_twoI} |> Thm.get_name_hint |> ThmC.cut_id)
   833 then () else error "first element of revset changed";
   834 if
   835 (revsets |> nth 1 |> nth 1 |> Rule.to_string) = "Thm (\"realpow_twoI\",?r1 \<up> 2 = ?r1 * ?r1)" andalso
   836 (revsets |> nth 1 |> nth 2 |> Rule.to_string) = "Thm (\"#: 9 = 3 \<up> 2\",9 = 3 \<up> 2)" andalso
   837 (revsets |> nth 1 |> nth 3 |> Rule.to_string) = "Thm (\"#: 6 * x = 2 * (3 * x)\",6 * x = 2 * (3 * x))" 
   838 andalso
   839 (revsets |> nth 1 |> nth 4 |> Rule.to_string) = "Thm (\"#: -3 * x = -1 * (3 * x)\",-3 * x = -1 * (3 * x))" 
   840 andalso
   841 (revsets |> nth 1 |> nth 5 |> Rule.to_string) = "Thm (\"#: 9 = 3 * 3\",9 = 3 * 3)" andalso
   842 (revsets |> nth 1 |> nth 6 |> Rule.to_string) = "Rls_ (\"sym_order_mult_rls_\")" andalso
   843 (revsets |> nth 1 |> nth 7 |> Rule.to_string) = 
   844   "Thm (\"sym_mult.assoc\",?a * (?b * ?c) = ?a * ?b * ?c)"
   845 then () else error "first 7 elements in revset changed"
   846 
   847 (** find the rule 'r' to apply to term 't' **)
   848 (*/------- WN1309: since cancel_ (accepted "-" between monomials) has been replaced by cancel_p_ 
   849   for Isabelle2013, we don't get a working revset, but non-termination:
   850 
   851   val SOME (r as (Thm (str, thm))) = nex revsets t;
   852   :
   853 ((3 * 3 + -1 * x * x) / (3 * 3 + 2 * 3 * x + x * x), 
   854   Rls_ ("sym_order_mult_rls_"), ((3 * 3 + -1 * (x * x)) / (3 * 3 + 2 * (3 * x) + x * x), []))", "
   855 ((3 * 3 + -1 * (x * x)) / (3 * 3 + 2 * (3 * x) + x * x), 
   856   Thm ("sym_mult.assoc", ""), ((3 * 3 + -1 * (x * x)) / (3 * 3 + 2 * 3 * x + x * x), []))", "
   857 ((3 * 3 + -1 * (x * x)) / (3 * 3 + 2 * 3 * x + x * x), 
   858   Thm ("sym_mult.assoc", ""), ((3 * 3 + -1 * x * x) / (3 * 3 + 2 * 3 * x + x * x), []))", "
   859 ((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), []))", "
   860  :
   861 ### Isabelle2002:
   862   Thm ("sym_#mult_2_3", "6 = 2 * 3")
   863 ### Isabelle2009-2 for cancel_ (not cancel_p_):
   864 if str = "sym_#power_Float ((3,0), (0,0)) __ ((2,0), (0,0))"
   865    andalso ThmC.string_of_thm thm = 
   866            (string_of_thm (Thm.make_thm @{theory "Isac_Knowledge"}
   867                (Trueprop $ (Thm.term_of o the o (TermC.parse thy)) "9 = 3 \<up> 2"))) then ()
   868 else error "rational.sml next_rule (9 - x \<up> 2) / (9 - 6 * x + x \<up> 2)";
   869 \---------------------------------------------------------------------------------------/*)
   870 
   871 (** check, if the rule 'r' applied by the user to 't' belongs to the ruleset;
   872   if the rule is OK, the term resulting from applying the rule is returned,too;
   873   there might be several rule applications inbetween,
   874   which are listed after the head in reverse order **)
   875 (*/-------------------------------------------- Isabelle2013: this gives "error id_of_thm";
   876   we don't repair this, because interaction within "reverse rewriting" never worked properly:
   877 
   878   val (r, (t, asm))::_ = loc revsets t r;
   879 if UnparseC.term t = "(9 - x \<up> 2) / (3 \<up> 2 + 6 * x + x \<up> 2)" andalso asm = []
   880 then () else error "rational.sml locate_rule (9 - x \<up> 2) / (9 - 6 * x + x \<up> 2)";
   881 
   882 (* find the next rule to apply *)
   883   val SOME (r as (Thm (str, thm))) = nex revsets t;
   884 if str = "sym_#power_Float ((3,0), (0,0)) __ ((2,0), (0,0))" andalso
   885    ThmC.string_of_thm thm = (string_of_thm (ThmC_Def.make_thm @{theory "Isac_Knowledge"}
   886                 (Trueprop $ (Thm.term_of o the o (TermC.parse thy)) "9 = 3 \<up> 2"))) then ()
   887 else error "rational.sml next_rule (9 - x \<up> 2) / (9 - 6 * x + x \<up> 2)";
   888 
   889 (*check the next rule*)
   890   val (r, (t, asm)) :: _ = loc revsets t r;
   891 if UnparseC.term t = "(3 \<up> 2 - x \<up> 2) / (3 \<up> 2 + 6 * x + x \<up> 2)" then ()
   892 else error "rational.sml locate_rule (9 - x \<up> 2) / (9 - 6 * x + x \<up> 2) II";
   893 
   894 (*find and check the next rules, rewrite*)
   895   val SOME r = nex revsets t;
   896   val (r,(t,asm))::_ = loc revsets t r;
   897 if UnparseC.term t = "(3 \<up> 2 - x \<up> 2) / (3 \<up> 2 + 2 * 3 * x + x \<up> 2)" then ()
   898 else error "rational.sml locate_rule II";
   899 
   900   val SOME r = nex revsets t;
   901   val (r,(t,asm))::_ = loc revsets t r;
   902 if UnparseC.term t = "(3 - x) * (3 + x) / (3 \<up> 2 + 2 * 3 * x + x \<up> 2)" then ()
   903 else error "rational.sml next_rule II";
   904 
   905   val SOME r = nex revsets t;
   906   val (r,(t,asm))::_ = loc revsets t r;
   907 if UnparseC.term t = "(3 - x) * (3 + x) / ((3 + x) * (3 + x))" then ()
   908 else error "rational.sml next_rule III";
   909 
   910   val SOME r = nex revsets t;
   911   val (r, (t, asm)) :: _ = loc revsets t r;
   912   val ss = UnparseC.term t;
   913 if ss = "(3 - x) / (3 + x)" andalso UnparseC.terms asm = "[\"3 + x ~= 0\"]" then ()
   914 else error "rational.sml: new behav. in rev-set cancel";
   915 \--------------------------------------------------------------------------------------/*)
   916 
   917 "-------- 'reverse-ruleset' cancel_p -----------------------------------------";
   918 "-------- 'reverse-ruleset' cancel_p -----------------------------------------";
   919 "-------- 'reverse-ruleset' cancel_p -----------------------------------------";
   920 (*WN130909: the example below shows, why "reverse rewriting" only worked for
   921   special cases.*)
   922 
   923 (*the term for which reverse rewriting is demonstrated*)
   924 val t = TermC.str2term "(9 + (-1)*x \<up> 2) / (9 + ((-6)*x + x \<up> 2))";
   925 val Rrls {scr=Rfuns {init_state=ini,locate_rule=loc,
   926 		       next_rule=nex,normal_form=nor,...},...} = cancel_p;
   927 
   928 (*normal_form produces the result in ONE step*)
   929 val SOME (t',_) = nor t; 
   930 UnparseC.term t' = "(3 + 1 * x) / (3 + -1 * x)";
   931 
   932 (*initialize the interpreter state used by the 'me'*)
   933 val SOME (t', asm) = cancel_p_ thy t;
   934 UnparseC.term t' = "(3 + x) / (3 + -1 * x)" (*true*);
   935 UnparseC.terms asm = "[\"3 + -1 * x ~= 0\"]" (*true*);
   936 val (t,_,revsets,_) = ini t;
   937 
   938 (* WN.10.10.02: dieser Fall terminiert nicht 
   939            (make_polynomial enth"alt zu viele rules)
   940 WN060823 'init_state' requires rewriting on specified location in the term
   941 default_print_depth 99; Rfuns; default_print_depth 3;
   942 WN060831 cycling "sym_order_mult_rls_" "sym_mult.assoc"
   943          as was with make_polynomial before ?!?*)
   944 
   945 val SOME r = nex revsets t;
   946 eq_Thm (r, Thm ("sym_#power_Float ((3,0), (0,0)) __ ((2,0), (0,0))", 
   947 		mk_thm thy "9 = 3 \<up> 2"));
   948 (*WN060831 *** id_of_thm
   949            Exception- ERROR raised ...
   950 val (r,(t,asm))::_ = loc revsets t r;
   951 UnparseC.term t;
   952 
   953   val SOME r = nex revsets t;
   954   val (r,(t,asm))::_ = loc revsets t r;
   955   UnparseC.term t;
   956 *)                    
   957 
   958 "-------- examples: rls norm_Rational ----------------------------------------";
   959 "-------- examples: rls norm_Rational ----------------------------------------";
   960 "-------- examples: rls norm_Rational ----------------------------------------";
   961 val t = TermC.str2term "(3*x+5)/18 - x/2  - -(3*x - 2)/9 = 0";
   962 val SOME (t',_) = rewrite_set_ thy false norm_Rational t; UnparseC.term t';
   963 if UnparseC.term t' = "1 / 18 = 0" then () else error "rational.sml 1";
   964 
   965 val t = TermC.str2term "(17*x - 51)/9 - (-(13*x - 3)/6) + 11 - (9*x - 7)/4 = 0";
   966 val SOME (t',_) = rewrite_set_ thy false norm_Rational t; UnparseC.term t';
   967 if UnparseC.term t' = "(237 + 65 * x) / 36 = 0" then () 
   968 else error "rational.sml 2";
   969 
   970 val t = TermC.str2term "(1/2 + (5*x)/2) \<up> 2 - ((13*x)/2 - 5/2) \<up> 2 - (6*x) \<up> 2 + 29";
   971 val SOME (t',_) = rewrite_set_ thy false norm_Rational t; UnparseC.term t';
   972 if UnparseC.term t' = "23 + 35 * x + -72 * x \<up> 2" then ()
   973 else error "rational.sml 3";
   974 
   975 (*Rewrite.trace_on:=true;*)
   976 val t = TermC.str2term "Not (6*x is_atom)";
   977 val SOME (t',_) = rewrite_set_ thy false powers_erls t; UnparseC.term t';
   978 "HOL.True";
   979 val t = TermC.str2term "1 < 2";
   980 val SOME (t',_) = rewrite_set_ thy false powers_erls t; UnparseC.term t';
   981 "HOL.True";
   982 
   983 val t = TermC.str2term "(6*x) \<up> 2";
   984 val SOME (t',_) = rewrite_ thy dummy_ord powers_erls false 
   985 			   (ThmC.numerals_to_Free @{thm realpow_def_atom}) t;
   986 if UnparseC.term t' = "6 * x * (6 * x) \<up> (2 + -1)" then ()
   987 else error "rational.sml powers_erls (6*x) \<up> 2";
   988 
   989 val t = TermC.str2term "-1 * (-2 * (5 / 2 * (13 * x / 2)))";
   990 val SOME (t',_) = rewrite_set_ thy false norm_Rational t; UnparseC.term t';
   991 if UnparseC.term t' = "65 * x / 2" then () else error "rational.sml 4";
   992 
   993 val t = TermC.str2term "1 - ((13*x)/2 - 5/2) \<up> 2";
   994 val SOME (t',_) = rewrite_set_ thy false norm_Rational t; UnparseC.term t';
   995 if UnparseC.term t' = "(-21 + 130 * x + -169 * x \<up> 2) / 4" then () 
   996 else error "rational.sml 5";
   997 
   998 (*SRAM Schalk I, p.92 Nr. 609a*)
   999 val t = TermC.str2term "2*(3 - x/5)/3 - 4*(1 - x/3) - x/3 - 2*(x/2 - 1/4)/27 +5/54";
  1000 val SOME (t',_) = rewrite_set_ thy false norm_Rational t; UnparseC.term t';
  1001 if UnparseC.term t' = "(-255 + 112 * x) / 135" then () 
  1002 else error "rational.sml 6";
  1003 
  1004 (*SRAM Schalk I, p.92 Nr. 610c*)
  1005 val t = TermC.str2term "((x- 1)/(x+1) + 1) / ((x- 1)/(x+1) - (x+1)/(x- 1)) - 2";
  1006 val SOME (t',_) = rewrite_set_ thy false norm_Rational t; UnparseC.term t';
  1007 if UnparseC.term t' = "(3 + x) / -2" then () else error "rational.sml 7";
  1008 
  1009 (*SRAM Schalk I, p.92 Nr. 476a*)
  1010 val t = TermC.str2term "(x \<up> 2/(1 - x \<up> 2) + 1)/(x/(1 - x) + 1) * (1 + x)";
  1011 (*. a/b : c/d translated to a/b * d/c .*)
  1012 val SOME (t',_) = rewrite_set_ thy false norm_Rational t; UnparseC.term t';
  1013 if UnparseC.term t' = "1" then () else error "rational.sml 8";
  1014 
  1015 (*Schalk I, p.92 Nr. 472a*)
  1016 val t = TermC.str2term "((8*x \<up> 2 - 32*y \<up> 2)/(2*x + 4*y))/((4*x - 8*y)/(x + y))";
  1017 val SOME (t',_) = rewrite_set_ thy false norm_Rational t; UnparseC.term t';
  1018 if UnparseC.term t' = "x + y" then () else error "rational.sml p.92 Nr. 472a";
  1019 
  1020 (*Schalk I, p.70 Nr. 480b: SEE rational.sml --- nonterminating rls norm_Rational ---*)
  1021 
  1022 (*WN130910 add_fractions_p exception Div raised + history:
  1023 ### WN.2.6.03 from rlang.sml 56a 
  1024 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)";
  1025 val NONE = rewrite_set_ thy false add_fractions_p t;
  1026 
  1027 THE ERROR ALREADY OCCURS IN THIS PART:
  1028 val t = TermC.str2term "(a + b * x) / (a + -1 * (b * x)) + (-1 * a + b * x) / (a + b * x)";
  1029 val NONE = add_fraction_p_ thy t;
  1030 
  1031 SEE Test_Some.thy: section {* add_fractions_p downto exception Div raised ===
  1032 *)
  1033 
  1034 "-------- rational numerals --------------------------------------------------";
  1035 "-------- rational numerals --------------------------------------------------";
  1036 "-------- rational numerals --------------------------------------------------";
  1037 (*SRA Schalk I, p.40 Nr. 164b *)
  1038 val t = TermC.str2term "(47/6 - 76/9 + 13/4)/(35/12)";
  1039 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1040 UnparseC.term t;
  1041 if UnparseC.term t = "19 / 21" then ()
  1042 else error "rational.sml: diff.behav. in norm_Rational_mg 1";
  1043 
  1044 (*SRA Schalk I, p.40 Nr. 166a *)
  1045 val t = TermC.str2term "((5/4)/(4+22/7) + 37/20)*(110/3 - 110/9 * 23/11)";
  1046 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1047 UnparseC.term t;
  1048 if UnparseC.term t = "45 / 2" then ()
  1049 else error "rational.sml: diff.behav. in norm_Rational_mg 2";
  1050 
  1051 "-------- examples cancellation from: Mathematik 1 Schalk --------------------";
  1052 "-------- examples cancellation from: Mathematik 1 Schalk --------------------";
  1053 "-------- examples cancellation from: Mathematik 1 Schalk --------------------";
  1054 (* e190c Stefan K.*)
  1055 val t = TermC.str2term "((1 + 9*a \<up> 2) * (1 + 3*a)) / ((3*a + 9*a \<up> 2) * (1 + 3*a))";
  1056 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1057 if UnparseC.term t = "(1 + 9 * a \<up> 2) / (3 * a + 9 * a \<up> 2)"
  1058 then () else error "rational.sml: diff.behav. in norm_Rational_mg 3";
  1059 
  1060 (* e192b Stefan K.*)
  1061 val t = TermC.str2term "(x \<up> 2 * (7*x + (-1)*y))  /  (y \<up> 2 * (7*x + (-1)*y))";
  1062 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1063 if UnparseC.term t = "x \<up> 2 / y \<up> 2"
  1064 then () else error "rational.sml: diff.behav. in norm_Rational_mg 4";
  1065 
  1066 (*SRC Schalk I, p.66 Nr. 379c *)
  1067 val t = TermC.str2term "(a - b)/(b - a)";
  1068 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1069 UnparseC.term t;
  1070 if UnparseC.term t = "-1"
  1071 then () else error "rational.sml: diff.behav. in norm_Rational_mg 5";
  1072 
  1073 (*SRC Schalk I, p.66 Nr. 380b *)
  1074 val t = TermC.str2term "15*(3*x + 3) * (4*x + 9)  /  (12*(2*x + 7) * (5*x + 5))";
  1075 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1076 if UnparseC.term t = "(27 + 12 * x) / (28 + 8 * x)"
  1077 then () else error "rational.sml: diff.behav. in norm_Rational_mg 6";
  1078 
  1079 (*Schalk I, p.60 Nr. 215c: was not cancelled with Isabelle2002 *)
  1080 val t = TermC.str2term "(a + b) \<up> 4 * (x - y)  /  ((x - y) \<up> 3 * (a + b) \<up> 2)";
  1081 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1082 if UnparseC.term t = "(a \<up> 2 + 2 * a * b + b \<up> 2) / (x \<up> 2 + -2 * x * y + y \<up> 2)"
  1083 then () else error "rational.sml: diff.behav. in norm_Rational_mg 7";
  1084 
  1085 (*SRC Schalk I, p.66 Nr. 381b *)
  1086 val t = TermC.str2term 
  1087 "(4*x \<up> 2 - 20*x + 25)/(2*x - 5) \<up> 3";
  1088 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1089 if UnparseC.term t = "1 / (-5 + 2 * x)"
  1090 then () else error "rational.sml: diff.behav. in norm_Rational_mg 9";
  1091 
  1092 (* e190c Stefan K.*)
  1093 val t = TermC.str2term "((1 + 9*a \<up> 2) * (1 + 3*a))  /  ((3*a + 9*a \<up> 2) * (1 + 3 * a))";
  1094 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1095 if UnparseC.term t =  "(1 + 9 * a \<up> 2) / (3 * a + 9 * a \<up> 2)"
  1096 then () else error "rational.sml: diff.behav. in norm_Rational_mg 3";
  1097 
  1098 (* e192b Stefan K.*)
  1099 val t = TermC.str2term "(x \<up> 2 * (7*x + (-1)*y))  /  (y \<up> 2 * (7*x + (-1)*y))";
  1100 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1101 if UnparseC.term t = "x \<up> 2 / y \<up> 2"
  1102 then () else error "rational.sml: diff.behav. in norm_Rational_mg 4";
  1103 
  1104 (*SRC Schalk I, p.66 Nr. 379c *)
  1105 val t = TermC.str2term "(a - b) / (b - a)";
  1106 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1107 if UnparseC.term t = "-1"
  1108 then () else error "rational.sml: diff.behav. in norm_Rational_mg 5";
  1109 
  1110 (*SRC Schalk I, p.66 Nr. 380b *)
  1111 val t = TermC.str2term "15*(3*x + 3) * (4*x + 9)  /  (12*(2*x + 7) * (5*x + 5))";
  1112 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1113 if UnparseC.term t = "(27 + 12 * x) / (28 + 8 * x)"
  1114 then () else error "rational.sml: diff.behav. in norm_Rational_mg 6";
  1115 
  1116 (*Schalk I, p.60 Nr. 215c *)
  1117 val t = TermC.str2term "(a + b) \<up> 4 * (x - y)  /  ((x - y) \<up> 3 * (a + b) \<up> 2)";
  1118 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1119 if UnparseC.term t = "(a \<up> 2 + 2 * a * b + b \<up> 2) / (x \<up> 2 + -2 * x * y + y \<up> 2)"
  1120 then () else error "Schalk I, p.60 Nr. 215c: with Isabelle2002 cancellation incomplete, changed";
  1121 
  1122 (* extreme example from somewhere *)
  1123 val t = TermC.str2term 
  1124     ("(a \<up> 4 * x  +  -1*a \<up> 4 * y  +  4*a \<up> 3 * b * x  +  -4*a \<up> 3 * b * y  + " ^
  1125       "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  + " ^
  1126       "b \<up> 4 * x  +  -1*b \<up> 4 * y) " ^
  1127   " / (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 + " ^
  1128       "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 + " ^
  1129       "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)")
  1130 val SOME (t, _) = rewrite_set_ thy false cancel_p t;
  1131 if UnparseC.term t = "(a \<up> 2 + 2 * a * b + b \<up> 2) / (x \<up> 2 + -2 * x * y + y \<up> 2)"
  1132 then () else error "with Isabelle2002: NONE -- now SOME changed";
  1133 
  1134 (*Schalk I, p.66 Nr. 381a *)
  1135 (* ATTENTION: here the rls is very slow. In Isabelle2002 this required 2 min *)
  1136 val t = TermC.str2term "18*(a + b) \<up> 3 * (a - b) \<up> 2 / (72*(a - b) \<up> 3 * (a + b) \<up> 2)";
  1137 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1138 if UnparseC.term t = "(a + b) / (4 * a + -4 * b)"
  1139 then () else error "rational.sml: diff.behav. in norm_Rational_mg 8";
  1140 
  1141 (*SRC Schalk I, p.66 Nr. 381b *)
  1142 val t = TermC.str2term "(4*x \<up> 2 - 20*x + 25) / (2*x - 5) \<up> 3";
  1143 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1144 if UnparseC.term t = "1 / (-5 + 2 * x)"
  1145 then () else error "rational.sml: diff.behav. in norm_Rational_mg 9";
  1146 
  1147 (*SRC Schalk I, p.66 Nr. 381c *)
  1148 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)";
  1149 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1150 if UnparseC.term t = "(1 + 9 * a \<up> 2) / (3 * a + 9 * a \<up> 2)"
  1151 then () else error "rational.sml: diff.behav. in norm_Rational_mg 10";
  1152 
  1153 (*SRC Schalk I, p.66 Nr. 383a *)
  1154 val t = TermC.str2term "(5*a \<up> 2 - 5*a*b) / (a - b) \<up> 2";
  1155 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1156 if UnparseC.term t = "-5 * a / (-1 * a + b)"
  1157 then () else error "rational.sml: diff.behav. in norm_Rational_mg 11";
  1158 
  1159 "----- NOT TERMINATING ?: worked before 0707xx";
  1160 val t = TermC.str2term "(a \<up> 2 - 1)*(b + 1) / ((b \<up> 2 - 1)*(a+1))";
  1161 (* WN130911 "exception Div raised" by 
  1162   cancel_p_ thy (TermC.str2term ("(-1 + -1 * b + a \<up> 2 + a \<up> 2 * b) /" ^
  1163                            "(-1 + -1 * a + b \<up> 2 + a * b \<up> 2)"))
  1164 
  1165 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1166 if UnparseC.term t = "(1 + -1 * a) / (1 + -1 * b)" then ()
  1167 else error "rational.sml MG tests 3e";
  1168 *)
  1169 
  1170 "-------- examples common denominator from: Mathematik 1 Schalk --------------";
  1171 "-------- examples common denominator from: Mathematik 1 Schalk --------------";
  1172 "-------- examples common denominator from: Mathematik 1 Schalk --------------";
  1173 (*SRA Schalk I, p.67 Nr. 403a *)
  1174 val t = TermC.str2term "4/x - 3/y - 1";
  1175 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1176 if UnparseC.term t = "(-3 * x + 4 * y + -1 * x * y) / (x * y)"
  1177 then () else error "rational.sml: diff.behav. in norm_Rational_mg 12";
  1178 
  1179 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)";
  1180 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1181 if UnparseC.term t = "4 / c"
  1182 then () else error "rational.sml: diff.behav. in norm_Rational_mg 13";
  1183 
  1184 (*SRA Schalk I, p.67 Nr. 410b *)
  1185 val t = TermC.str2term "1/(x+1) + 1/(x+2) - 2/(x+3)";
  1186 (* WN130911 non-termination due to non-termination of
  1187   cancel_p_ thy (TermC.str2term "(5 + 3 * x) / (6 + 11 * x + 6 * x \<up> 2 + x \<up> 3)")
  1188 
  1189 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1190 if UnparseC.term t = "(5 + 3 * x) / (6 + 11 * x + 6 * x \<up> 2 + x \<up> 3)"
  1191 then () else error "rational.sml: diff.behav. in norm_Rational_mg 14";
  1192 *)
  1193 
  1194 (*SRA Schalk I, p.67 Nr. 413b *)
  1195 val t = TermC.str2term "(1 + x)/(1 - x)  -  (1 - x)/(1 + x)  +  2*x/(1 - x \<up> 2)";
  1196 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1197 if UnparseC.term t = "6 * x / (1 + -1 * x \<up> 2)"
  1198 then () else error "rational.sml: diff.behav. in norm_Rational_mg 15";
  1199 
  1200 (*SRA Schalk I, p.68 Nr. 414a *)
  1201 val t = TermC.str2term "(x + 2)/(x - 1)  +  (x - 3)/(x - 2)  -  (x + 1)/((x - 1)*(x - 2))";
  1202 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1203 if UnparseC.term t ="(-2 + -5 * x + 2 * x \<up> 2) / (2 + -3 * x + x \<up> 2)"
  1204 then () else error "rational.sml: diff.behav. in norm_Rational_mg 16";
  1205 
  1206 (*SRA Schalk I, p.68 Nr. 428b *)
  1207 val t = TermC.str2term 
  1208   "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";
  1209 (* WN130911 non-termination due to non-termination of
  1210   cancel_p_ thy (TermC.str2term "(4 + -4 * b \<up> 2) / (a \<up> 4 + -2 * (a \<up> 2 * b \<up> 2) + b \<up> 4)")
  1211 
  1212 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1213 if UnparseC.term t = "4 / (a \<up> 4 + -2 * a \<up> 2 * b \<up> 2 + b \<up> 4)"
  1214 then () else error "rational.sml: diff.behav. in norm_Rational_mg 18";
  1215 *)
  1216 
  1217 (*SRA Schalk I, p.68 Nr. 430b *)
  1218 val t = TermC.str2term 
  1219   "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";
  1220 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1221 if UnparseC.term t = "a + 3 * b"
  1222 then () else error "rational.sml: diff.behav. in norm_Rational_mg 19";
  1223 
  1224 (*SRA Schalk I, p.68 Nr. 432 *)
  1225 val t = TermC.str2term 
  1226   ("(a \<up> 2 + a*b) / (a \<up> 2 - b \<up> 2)  -  (b \<up> 2 - a*b) / (b \<up> 2 - a \<up> 2)  +  " ^
  1227   "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)  -  " ^
  1228   "2*b \<up> 2 / (a \<up> 2 - b \<up> 2)");
  1229 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1230 if UnparseC.term t = (*"0" ..isabisac15 | Isabelle2017..*)  "0 / (a \<up> 2 + -1 * b \<up> 2)"
  1231 then () else error "rational.sml: diff.behav. in norm_Rational_mg 20";
  1232 
  1233 (* some example *)
  1234 val t = TermC.str2term "3*a / (a*b)  +  x/y";
  1235 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1236 if UnparseC.term t = "(3 * y + b * x) / (b * y)"
  1237 then () else error "rational.sml: diff.behav. in norm_Rational_mg 21";
  1238 
  1239 "-------- examples multiply and cancel from: Mathematik 1 Schalk -------------";
  1240 "-------- examples multiply and cancel from: Mathematik 1 Schalk -------------";
  1241 "-------- examples multiply and cancel from: Mathematik 1 Schalk -------------";
  1242 (*------- SRM Schalk I, p.68 Nr. 436a *)
  1243 val t = TermC.str2term "3*(x+y) / (15*(x - y))  *   25*(x - y) \<up> 2 / (18*(x + y) \<up> 2)";
  1244 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1245 if UnparseC.term t = "(-5 * x + 5 * y) / (-18 * x + -18 * y)"
  1246 then () else error "rational.sml: diff.behav. in norm_Rational_mg 22";
  1247 
  1248 (*------- SRM.test Schalk I, p.68 Nr. 436b *)
  1249 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";
  1250 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1251 if UnparseC.term t = "5 * a / (a + -1 * b)"
  1252 then () else error "rational.sml: diff.behav. in norm_Rational_mg 23";
  1253 
  1254 (*------- Schalk I, p.68 Nr. 437a *)
  1255 val t = TermC.str2term "(3*a - 4*b) / (4*c+3*e)  *  (3*a+4*b)/(9*a \<up> 2 - 16*b \<up> 2)";
  1256 (* raises an exception for unclear reasons:
  1257 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1258 :
  1259 ###  rls: cancel_p on: (9 * a \<up> 2 + -16 * b \<up> 2) / (4 * c + 3 * e) /
  1260 (9 * a \<up> 2 + -16 * b \<up> 2) 
  1261 exception Div raised
  1262 
  1263 BUT
  1264 val t = TermC.str2term 
  1265   ("(9 * a \<up> 2 + -16 * b \<up> 2) / (4 * c + 3 * e) /" ^
  1266   "(9 * a \<up> 2 + -16 * b \<up> 2)");
  1267 NONE = cancel_p_ thy t;
  1268 
  1269 if UnparseC.term t = "1 / (4 * c + 3 * e)" then ()
  1270 else error "rational.sml: diff.behav. in norm_Rational_mg 24";
  1271 *)
  1272 
  1273 "----- S.K. corrected non-termination 060904";
  1274 val t = TermC.str2term "(3*a - 4*b) * (3*a+4*b)/((4*c+3*e)*(9*a \<up> 2 - 16*b \<up> 2))";
  1275 val SOME (t, _) = rewrite_set_ thy false make_polynomial t;
  1276 if UnparseC.term t = 
  1277   "(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)"
  1278 (*"(9 * a \<up> 2 + -16 * b \<up> 2) / (36 * a \<up> 2 * c + 27 * a \<up> 2 * e + -64 * b \<up> 2 * c + -48 * b \<up> 2 * e)"*)
  1279 then () else error "rational.sml: S.K.8..corrected 060904-6";
  1280 
  1281 "----- S.K. corrected non-termination of cancel_p_";
  1282 val t'' = TermC.str2term ("(9 * a \<up> 2 + -16 * b \<up> 2) /" ^
  1283   "(36 * a \<up> 2 * c + (27 * a \<up> 2 * e + (-64 * b \<up> 2 * c + -48 * b \<up> 2 * e)))");
  1284 (* /--- DOES NOT TERMINATE AT TRANSITION isabisac15 --> Isabelle2017 --------------------------\
  1285 val SOME (t',_) = rewrite_set_ thy false cancel_p t'';
  1286 if UnparseC.term t' = "1 / (4 * c + 3 * e)"
  1287 then () else error "rational.sml: diff.behav. in cancel_p S.K.8";
  1288    \--- DOES NOT TERMINATE AT TRANSITION isabisac15 --> Isabelle2017 --------------------------/*)
  1289 
  1290 (*------- Schalk I, p.68 Nr. 437b*)
  1291 val t = TermC.str2term "(a + b)/(x \<up> 2 - y \<up> 2) * ((x - y) \<up> 2/(a \<up> 2 - b \<up> 2))";
  1292 (*val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1293 :
  1294 ####  rls: cancel_p on: (a * x \<up> 2 + -2 * (a * (x * y)) + a * y \<up> 2 + b * x \<up> 2 +
  1295  -2 * (b * (x * y)) +
  1296  b * y \<up> 2) /
  1297 (a \<up> 2 * x \<up> 2 + -1 * (a \<up> 2 * y \<up> 2) + -1 * (b \<up> 2 * x \<up> 2) +
  1298  b \<up> 2 * y \<up> 2) 
  1299 exception Div raised
  1300 *)
  1301 
  1302 (*------- SRM Schalk I, p.68 Nr. 438a *)
  1303 val t = TermC.str2term "x*y / (x*y - y \<up> 2)  *  (x \<up> 2 - x*y)";
  1304 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1305 if UnparseC.term t = "x \<up> 2"
  1306 then () else error "rational.sml: diff.behav. in norm_Rational_mg 24";
  1307 
  1308 (*------- SRM Schalk I, p.68 Nr. 439b *)
  1309 val t = TermC.str2term "(4*x \<up> 2 + 4*x + 1)  *  ((x \<up> 2 - 2*x \<up> 3) / (4*x \<up> 2 + 2*x))";
  1310 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1311 if UnparseC.term t = "(x + -4 * x \<up> 3) / 2"
  1312 then () else error "rational.sml: diff.behav. in norm_Rational_mg 25";
  1313 
  1314 (*------- SRM Schalk I, p.68 Nr. 440a *)
  1315 val t = TermC.str2term "(x \<up> 2 - 2*x) / (x \<up> 2 - 3*x)  *  (x - 3) \<up> 2 / (x \<up> 2 - 4)";
  1316 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1317 if UnparseC.term t = "(-3 + x) / (2 + x)"
  1318 then () else error "rational.sml: diff.behav. in norm_Rational_mg 26";
  1319 
  1320 "----- Schalk I, p.68 Nr. 440b SK11 works since 0707xx";
  1321 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)";
  1322 (* WN130911 non-termination for unclear reasons:
  1323 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1324 
  1325 ... ENDS WITH THIS TRACE:
  1326 :
  1327 ###  rls: cancel_p on: (-9 * (a \<up> 3 * b) + -9 * (a \<up> 2 * b \<up> 2) + a \<up> 5 * b +
  1328  a \<up> 4 * b \<up> 2) /
  1329 (a \<up> 3 * b + -1 * (a * b \<up> 3)) /
  1330 (3 + a)
  1331 BUT THIS IS CORRECTLY RECOGNISED 
  1332 val t = TermC.str2term 
  1333   ("(-9 * (a \<up> 3 * b) + -9 * (a \<up> 2 * b \<up> 2) + a \<up> 5 * b + a \<up> 4 * b \<up> 2)  /" ^
  1334   "(a \<up> 3 * b + -1 * (a * b \<up> 3))  /  (3 + (a::real))");
  1335 AS
  1336 NONE = cancel_p_ thy t;
  1337 
  1338 if UnparseC.term t = "(-3 * a + a \<up> 2) / (a + -1 * b)" then ()
  1339 else error "rational.sml: diff.behav. in norm_Rational 27";
  1340 *)
  1341 
  1342 "----- SK12 works since 0707xx";
  1343 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))";
  1344 (* WN130911 non-termination due to non-termination of
  1345   cancel_p_ thy (TermC.str2term "(4 + -4 * b \<up> 2) / (a \<up> 4 + -2 * (a \<up> 2 * b \<up> 2) + b \<up> 4)")
  1346 
  1347 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1348 if UnparseC.term t' = "(-3 * a + a \<up> 2) / (a + -1 * b)" then ()
  1349 else error "rational.sml: diff.behav. in norm_Rational 28";
  1350 *)
  1351 
  1352 "-------- examples common denominator and multiplication from: Schalk --------";
  1353 "-------- examples common denominator and multiplication from: Schalk --------";
  1354 "-------- examples common denominator and multiplication from: Schalk --------";
  1355 (*------- SRAM Schalk I, p.69 Nr. 441b *)
  1356 val t = TermC.str2term "(4*a/3 + 3*b \<up> 2/a \<up> 3 + b/(4*a))*(4*b/(3*a))";
  1357 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1358 if UnparseC.term t = "(36 * b \<up> 3 + 3 * a \<up> 2 * b \<up> 2 + 16 * a \<up> 4 * b) / (9 * a \<up> 4)"
  1359 then () else error "rational.sml: diff.behav. in norm_Rational_mg 28";
  1360 
  1361 (*------- SRAM Schalk I, p.69 Nr. 442b *)
  1362 val t = TermC.str2term ("(15*a \<up> 2/x \<up> 3 - 5*b \<up> 4/x \<up> 2 + 25*c \<up> 2/x) * " ^
  1363   "(x \<up> 3/(5*a*b \<up> 3*c \<up> 3)) + 1/c \<up> 3 * (b*x/a - 3*a/b \<up> 3)");
  1364 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1365 if UnparseC.term t = "5 * x \<up> 2 / (a * b \<up> 3 * c)"
  1366 then () else error "rational.sml: diff.behav. in norm_Rational_mg 29";
  1367 
  1368 (*------- SRAM Schalk I, p.69 Nr. 443b *)
  1369 val t = TermC.str2term "(a/2 + b/3) * (b/3 - a/2)";
  1370 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1371 if UnparseC.term t = "(-9 * a \<up> 2 + 4 * b \<up> 2) / 36"
  1372 then () else error "rational.sml: diff.behav. in norm_Rational_mg 30";
  1373 
  1374 (*------- SRAM Schalk I, p.69 Nr. 445b *)
  1375 val t = TermC.str2term "(a \<up> 2/9 + 2*a/(3*b) + 4/b \<up> 2)*(a/3 - 2/b) + 8/b \<up> 3";
  1376 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1377 if UnparseC.term t = "a \<up> 3 / 27"
  1378 then () else error "rational.sml: diff.behav. in norm_Rational_mg 31";
  1379 
  1380 (*------- SRAM Schalk I, p.69 Nr. 446b *)
  1381 val t = TermC.str2term "(x/(5*x + 4*y) - y/(5*x - 4*y) + 1)*(25*x \<up> 2 - 16*y \<up> 2)";
  1382 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1383 if UnparseC.term t = (*"30 * x \<up> 2 + -9 * x * y + -20 * y \<up> 2" ..isabisac15 | Isabelle2017..*)
  1384                   "(-30 * x \<up> 2 + 9 * x * y + 20 * y \<up> 2) / -1"
  1385 then () else error "rational.sml: diff.behav. in norm_Rational_mg 32";
  1386 
  1387 (*------- SRAM Schalk I, p.69 Nr. 449a *)(*Achtung: rechnet ca 8 Sekunden*)
  1388 val t = TermC.str2term 
  1389 "(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)";
  1390 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1391 if UnparseC.term t = "(-81 * x \<up> 4 + 16 * x \<up> 8 * y \<up> 4) / (81 * y \<up> 8)"
  1392 then () else error "rational.sml: diff.behav. in norm_Rational_mg 33";
  1393 
  1394 (*------- SRAM Schalk I, p.69 Nr. 450a *)
  1395 val t = TermC.str2term 
  1396 "(4*x/(3*y)+2*y/(3*x)) \<up> 2 - (2*y/(3*x) - 2*x/y)*(2*y/(3*x)+2*x/y)";
  1397 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1398 if UnparseC.term t = "(52 * x \<up> 2 + 16 * y \<up> 2) / (9 * y \<up> 2)"
  1399 then () else error "rational.sml: diff.behav. in norm_Rational_mg 34";
  1400 
  1401 (*------- SRAM Schalk I, p.69 Nr. 442b --- abgewandelt*)
  1402 val t = TermC.str2term 
  1403   ("(15*a \<up> 4/(a*x \<up> 3)  -  5*a*((b \<up> 4 - 5*c \<up> 2*x) / x \<up> 2))  *  " ^
  1404   "(x \<up> 3/(5*a*b \<up> 3*c \<up> 3))   +   a/c \<up> 3 * (x*(b/a) - 3*b*(a/b \<up> 4))");
  1405 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1406 if UnparseC.term t = "5 * x \<up> 2 / (b \<up> 3 * c)"
  1407 then () else error "rational.sml: diff.behav. in norm_Rational_mg 53";
  1408 
  1409 
  1410 "-------- examples double fractions from: Mathematik 1 Schalk ----------------";
  1411 "-------- examples double fractions from: Mathematik 1 Schalk ----------------";
  1412 "-------- examples double fractions from: Mathematik 1 Schalk ----------------";
  1413 "----- SRD Schalk I, p.69 Nr. 454b";
  1414 val t = TermC.str2term "((2 - x)/(2*a)) / (2*a/(x - 2))";
  1415 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1416 if UnparseC.term t = "(-4 + 4 * x + -1 * x \<up> 2) / (4 * a \<up> 2)"
  1417 then () else error "rational.sml: diff.behav. in norm_Rational_mg 35";
  1418 
  1419 "----- SRD Schalk I, p.69 Nr. 455a";
  1420 val t = TermC.str2term "(a \<up> 2 + 1)/(a \<up> 2 - 1) / ((a+1)/(a - 1))";
  1421 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1422 if UnparseC.term t = "(1 + a \<up> 2) / (1 + 2 * a + a \<up> 2)" then ()
  1423 else error "rational.sml: diff.behav. in norm_Rational_mg 36";
  1424 
  1425 "----- Schalk I, p.69 Nr. 455b";
  1426 val t = TermC.str2term "(x \<up> 2 - 4)/(y \<up> 2 - 9)/((2+x)/(3 - y))";
  1427 (* WN130911 non-termination due to non-termination of
  1428   cancel_p_ thy (TermC.str2term ("(-12 + 4 * y + 3 * x \<up> 2 + -1 * (x \<up> 2 * y)) /" ^
  1429                            "(-18 + -9 * x + 2 * y \<up> 2 + x * y \<up> 2)"))
  1430 
  1431 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1432 if UnparseC.term t = "(2 + -1 * x) / (3 + y)" then ()
  1433 else error "rational.sml: diff.behav. in norm_Rational_mg 37";
  1434 *)
  1435 
  1436 "----- SK060904-1a non-termination of cancel_p_ ?: worked before 0707xx";
  1437 val t = TermC.str2term "(x \<up> 2 - 4)*(3 - y) / ((y \<up> 2 - 9)*(2+x))";
  1438 (* WN130911 non-termination due to non-termination of
  1439   cancel_p_ thy (TermC.str2term ("(-12 + 4 * y + 3 * x \<up> 2 + -1 * (x \<up> 2 * y)) /" ^
  1440                            "(-18 + -9 * x + 2 * y \<up> 2 + x * y \<up> 2)"))
  1441 
  1442 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1443 if UnparseC.term t = "(2 + -1 * x) / (3 + y)" then ()
  1444 else error "rational.sml: diff.behav. in norm_Rational_mg 37b";
  1445 *)
  1446 
  1447 "----- ?: worked before 0707xx";
  1448 val t = TermC.str2term "(3 + -1 * y) / (-9 + y \<up> 2)";
  1449 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1450 if UnparseC.term t = "-1 / (3 + y)"
  1451 then () else error "rational.sml: -1 / (3 + y) norm_Rational";
  1452 
  1453 "----- SRD Schalk I, p.69 Nr. 456b";
  1454 val t = TermC.str2term "(b \<up> 3 - b \<up> 2) / (b \<up> 2+b) / (b \<up> 2 - 1)";
  1455 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1456 if UnparseC.term t = "b / (1 + 2 * b + b \<up> 2)"
  1457 then () else error "rational.sml: diff.behav. in norm_Rational_mg 38";
  1458 
  1459 "----- SRD Schalk I, p.69 Nr. 457b";
  1460 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))";
  1461 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1462 if UnparseC.term t = "8 * a \<up> 2 + -6 * a * b + -12 * a \<up> 2 * b + 9 * a * b \<up> 2"
  1463 then () else error "rational.sml: diff.behav. in norm_Rational_mg 39";
  1464 
  1465 "----- Schalk I, p.69 Nr. 458b works since 0707";
  1466 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)))";
  1467 (*val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1468 :
  1469 ###  rls: cancel_p on: (-1 * a \<up> 2 + 2 * (a \<up> 2 * x)) / (a * x + -1 * (b * x)) /
  1470 ((-1 * b \<up> 2 + 2 * (b \<up> 2 * x)) / (a * x + -1 * (b * x))) 
  1471 exception Div raised
  1472 
  1473 BUT
  1474 val t = TermC.str2term 
  1475   ("(-1 * a \<up> 2 + 2 * (a \<up> 2 * x)) / (a * x + -1 * (b * x)) /" ^
  1476   "((-1 * b \<up> 2 + 2 * (b \<up> 2 * x)) / (a * x + -1 * (b * x)))");
  1477 NONE = cancel_p_ thy t;
  1478 
  1479 if UnparseC.term t = "a \<up> 2 / b \<up> 2" then ()
  1480 else error "rational.sml: diff.behav. in norm_Rational_mg 39b";
  1481 *)
  1482 
  1483 "----- SRD Schalk I, p.69 Nr. 459b";
  1484 val t = TermC.str2term "(a \<up> 2 - b \<up> 2)/(a*b) / (4*(a+b) \<up> 2/a)";
  1485 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1486 if UnparseC.term t = "(a + -1 * b) / (4 * a * b + 4 * b \<up> 2)" then ()
  1487 else error "rational.sml: diff.behav. in norm_Rational_mg 41";
  1488 
  1489 "----- Schalk I, p.69 Nr. 460b nonterm.SK";
  1490 val t = TermC.str2term "(9*(x \<up> 2 - 8*x + 16) / (4*(y \<up> 2 - 2*y + 1))) / ((3*x - 12) / (16*y - 16))";
  1491 (*val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1492 exception Div raised
  1493 
  1494 BUT
  1495 val t = TermC.str2term 
  1496   ("(144 + -72 * x + 9 * x \<up> 2) / (4 + -8 * y + 4 * y \<up> 2) /" ^
  1497   "((-12 + 3 * x) / (-16 + 16 * y))");
  1498 NONE = cancel_p_ thy t;
  1499 
  1500 if UnparseC.term t = !!!!!!!!!!!!!!!!!!!!!!!!!
  1501 then () else error "rational.sml: diff.behav. in norm_Rational_mg 42";
  1502 *)
  1503 
  1504 "----- some variant of the above; was non-terminating before";
  1505 val t = TermC.str2term "9*(x \<up> 2 - 8*x+16)*(16*y - 16)/(4*(y \<up> 2 - 2*y+1)*(3*x - 12))";
  1506 val SOME (t , _) = rewrite_set_ thy false norm_Rational t;
  1507 if UnparseC.term t = "(48 + -12 * x) / (1 + -1 * y)"
  1508 then () else error "some variant of the above; was non-terminating before";
  1509 
  1510 "----- SRD Schalk I, p.70 Nr. 472a";
  1511 val t = TermC.str2term ("((8*x \<up> 2 - 32*y \<up> 2) / (2*x + 4*y))  /  ((4*x - 8*y) / (x + y))");
  1512 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1513 if UnparseC.term t = "x + y"
  1514 then () else error "rational.sml: diff.behav. in norm_Rational_mg 43";
  1515 
  1516 "----- Schalk I, p.70 Nr. 478b ----- Rechenzeit: 5 sec";
  1517 val t = TermC.str2term ("(a - (a*b + b \<up> 2)/(a+b))/(b+(a - b)/(1+(a+b)/(a - b))) / " ^
  1518 		 "((a - a \<up> 2/(a+b))/(a+(a*b)/(a - b)))");
  1519 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1520 if UnparseC.term t = "(2 * a \<up> 3 + 2 * a \<up> 2 * b) / (a \<up> 2 * b + b \<up> 3)"
  1521 then () else error "rational.sml: diff.behav. in norm_Rational_mg 51";
  1522 
  1523 (*SRD Schalk I, p.69 Nr. 461a *)
  1524 val t = TermC.str2term "(2/(x+3) + 2/(x - 3)) / (8*x/(x \<up> 2 - 9))";
  1525 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1526 if UnparseC.term t = "1 / 2"
  1527 then () else error "rational.sml: diff.behav. in norm_Rational_mg 44";
  1528 
  1529 (*SRD Schalk I, p.69 Nr. 464b *)
  1530 val t = TermC.str2term "(a - a/(a - 2)) / (a + a/(a - 2))";
  1531 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1532 if UnparseC.term t = "(-3 + a) / (-1 + a)"
  1533 then () else error "rational.sml: diff.behav. in norm_Rational_mg 45";
  1534 
  1535 (*SRD Schalk I, p.69 Nr. 465b *)
  1536 val t = TermC.str2term "((x+3*y)/9 + (4*y \<up> 2 - 9*z \<up> 2)/(16*x))   /   (x/9 + y/6 + z/4)";
  1537 (* WN130911 non-termination due to non-termination of
  1538   cancel_p_ thy (TermC.str2term 
  1539     ("("(576 * x \<up> 2 + 1728 * (x * y) + 1296 * y \<up> 2 + -2916 * z \<up> 2) /" ^
  1540       "(576 * x \<up> 2 + 864 * (x * y) + 1296 * (x * z))"))
  1541 
  1542 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1543 if UnparseC.term t = "(4 * x + 6 * y + -9 * z) / (4 * x)"
  1544 then () else error "rational.sml: diff.behav. in norm_Rational_mg 46";
  1545 *)
  1546 
  1547 (*SRD Schalk I, p.69 Nr. 466b *)
  1548 val t = TermC.str2term "((1 - 7*(x - 2)/(x \<up> 2 - 4)) / (6/(x+2))) / (3/(x+5)+30/(x \<up> 2 - 25))";
  1549 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1550 if UnparseC.term t = "(25 + -10 * x + x \<up> 2) / 18"
  1551 then () else error "rational.sml: diff.behav. in norm_Rational_mg 47";
  1552 
  1553 (*SRD Schalk I, p.70 Nr. 469 *)
  1554 val t = TermC.str2term ("3*b \<up> 2 / (4*a \<up> 2 - 8*a*b + 4*b \<up> 2) / " ^
  1555   "(a / (a \<up> 2*b - b \<up> 3)  +  (a - b) / (4*a*b \<up> 2 + 4*b \<up> 3)  -  1 / (4*b \<up> 2))");
  1556 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1557 if UnparseC.term t = "-3 * b \<up> 3 / (-2 * a + 2 * b)"
  1558 then () else error "rational.sml: diff.behav. in norm_Rational_mg 48";
  1559 
  1560 "-------- me Schalk I No.186 -------------------------------------------------";
  1561 "-------- me Schalk I No.186 -------------------------------------------------";
  1562 "-------- me Schalk I No.186 -------------------------------------------------";
  1563 val fmz = ["Term ((14 * x * y) / ( x * y ))", "normalform N"];
  1564 val (dI',pI',mI') =
  1565   ("Rational",["rational", "simplification"],
  1566    ["simplification", "of_rationals"]);
  1567 val p = e_pos'; val c = []; 
  1568 val (p,_,f,nxt,_,pt) = CalcTreeTEST [(fmz, (dI',pI',mI'))];
  1569 val (p,_,f,nxt,_,pt) = me nxt p c pt;
  1570 val (p,_,f,nxt,_,pt) = me nxt p c pt;
  1571 val (p,_,f,nxt,_,pt) = me nxt p c pt;
  1572 val (p,_,f,nxt,_,pt) = me nxt p c pt;
  1573 val (p,_,f,nxt,_,pt) = me nxt p c pt;
  1574 val (p,_,f,nxt,_,pt) = me nxt p c pt;
  1575 val (p,_,f,nxt,_,pt) = me nxt p c pt;
  1576 val (p,_,f,nxt,_,pt) = me nxt p c pt; f2str f;
  1577 val (p,_,f,nxt,_,pt) = me nxt p c pt; f2str f;
  1578 val (p,_,f,nxt,_,pt) = me nxt p c pt; f2str f;(*++ for explicit script*)
  1579 val (p,_,f,nxt,_,pt) = me nxt p c pt; f2str f;(*++ for explicit script*)
  1580 case (f2str f, nxt) of
  1581     ("14", ("End_Proof'", _)) => ()
  1582   | _ => error "rational.sml diff.behav. in me Schalk I No.186";
  1583 
  1584 "-------- interSteps ..Simp_Rat_Double_No-1.xml ------------------------------";
  1585 "-------- interSteps ..Simp_Rat_Double_No-1.xml ------------------------------";
  1586 "-------- interSteps ..Simp_Rat_Double_No-1.xml ------------------------------";
  1587 reset_states ();
  1588 CalcTree [(["Term (((2 - x)/(2*a)) / (2*a/(x - 2)))", "normalform N"], 
  1589   ("Rational", ["rational", "simplification"], ["simplification", "of_rationals"]))];
  1590 Iterator 1;
  1591 moveActiveRoot 1;
  1592 autoCalculate 1 CompleteCalc;
  1593 val ((pt, p), _) = get_calc 1; 
  1594 (*
  1595 Test_Tool.show_pt pt;
  1596 [
  1597 (([], Frm), Simplify ((2 - x) / (2 * a) / (2 * a / (x - 2)))),
  1598 (([1], Frm), (2 - x) / (2 * a) / (2 * a / (x - 2))),
  1599 (([1], Res), (2 + -1 * x) / (2 * a) / (2 * a / (x + -1 * 2))),
  1600 (([2], Res), (2 + -1 * x) / (2 * a) / (2 * a / (-2 + x))),
  1601 (([3], Res), (2 + -1 * x) * (-2 + x) / (2 * a * (2 * a))),
  1602 (([4], Res), (-4 + 4 * x + -1 * x \<up> 2) / (4 * a \<up> 2)),
  1603 (([], Res), (-4 + 4 * x + -1 * x \<up> 2) / (4 * a \<up> 2))] 
  1604 *)
  1605 interSteps 1 ([1], Res);
  1606 val ((pt, p), _) = get_calc 1; 
  1607 (*Test_Tool.show_pt pt;
  1608 [
  1609 (([], Frm), Simplify ((2 - x) / (2 * a) / (2 * a / (x - 2)))),
  1610 (([1], Frm), (2 - x) / (2 * a) / (2 * a / (x - 2))),
  1611 (([1,1], Frm), (2 - x) / (2 * a) / (2 * a / (x - 2))),
  1612 (([1,1], Res), (2 - x) / (2 * a) / (2 * a / (x + -1 * 2))),
  1613 (([1,2], Res), (2 + -1 * x) / (2 * a) / (2 * a / (x + -1 * 2))),
  1614 (([1], Res), (2 + -1 * x) / (2 * a) / (2 * a / (x + -1 * 2))),
  1615 (([2], Res), (2 + -1 * x) / (2 * a) / (2 * a / (-2 + x))),
  1616 (([3], Res), (2 + -1 * x) * (-2 + x) / (2 * a * (2 * a))),
  1617 (([4], Res), (-4 + 4 * x + -1 * x \<up> 2) / (4 * a \<up> 2)),
  1618 (([], Res), (-4 + 4 * x + -1 * x \<up> 2) / (4 * a \<up> 2))] 
  1619 *)
  1620 val (t, asm) = get_obj g_result pt [1, 1];
  1621 if UnparseC.term t = "(2 - x) / (2 * a) / (2 * a / (x + -1 * 2))" andalso UnparseC.terms asm = "[]"
  1622 then () else error "2nd interSteps ..Simp_Rat_Double_No-1 changed on [1, 1]";
  1623 val (t, asm) = get_obj g_result pt [1, 2];
  1624 if UnparseC.term t = "(2 + -1 * x) / (2 * a) / (2 * a / (x + -1 * 2))" andalso UnparseC.terms asm = "[]"
  1625 then () else error "3rd interSteps ..Simp_Rat_Double_No-1 changed on [1, 2]";
  1626 
  1627 
  1628 "-------- interSteps ..Simp_Rat_Cancel_No-1.xml ------------------------------";
  1629 "-------- interSteps ..Simp_Rat_Cancel_No-1.xml ------------------------------";
  1630 "-------- interSteps ..Simp_Rat_Cancel_No-1.xml ------------------------------";
  1631 reset_states ();
  1632 CalcTree [(["Term ((a^2 + -1*b^2) / (a^2 + -2*a*b + b^2))", "normalform N"], 
  1633   ("Rational", ["rational", "simplification"], ["simplification", "of_rationals"]))];
  1634 Iterator 1;
  1635 moveActiveRoot 1;
  1636 autoCalculate 1 CompleteCalc;
  1637 val ((pt, p), _) = get_calc 1;
  1638 (*Test_Tool.show_pt pt;
  1639 [
  1640 (([], Frm), Simplify ((a \<up> 2 + -1 * b \<up> 2) / (a \<up> 2 + -2 * a * b + b \<up> 2))),
  1641 (([1], Frm), (a \<up> 2 + -1 * b \<up> 2) / (a \<up> 2 + -2 * a * b + b \<up> 2)),
  1642 (([1], Res), (a \<up> 2 + -1 * b \<up> 2) / (a \<up> 2 + -2 * (a * b) + b \<up> 2)),
  1643 (([2], Res), (a + b) / (a + -1 * b)),
  1644 (([], Res), (a + b) / (a + -1 * b))] 
  1645 *)
  1646 interSteps 1 ([2], Res);
  1647 val ((pt, p), _) = get_calc 1;
  1648 (*Test_Tool.show_pt pt;
  1649 [
  1650 (([], Frm), Simplify ((a \<up> 2 + -1 * b \<up> 2) / (a \<up> 2 + -2 * a * b + b \<up> 2))),
  1651 (([1], Frm), (a \<up> 2 + -1 * b \<up> 2) / (a \<up> 2 + -2 * a * b + b \<up> 2)),
  1652 (([1], Res), (a \<up> 2 + -1 * b \<up> 2) / (a \<up> 2 + -2 * (a * b) + b \<up> 2)),
  1653 (([2,1], Frm), (a \<up> 2 + -1 * b \<up> 2) / (a \<up> 2 + -2 * (a * b) + b \<up> 2)),
  1654 (([2,1], Res), (a + b) / (a + -1 * b)),
  1655 (([2], Res), (a + b) / (a + -1 * b)),
  1656 (([], Res), (a + b) / (a + -1 * b))] 
  1657 *)
  1658 interSteps 1 ([2,1],Res);
  1659 val ((pt, p), _) = get_calc 1; 
  1660 (*Test_Tool.show_pt pt;
  1661 [
  1662 (([], Frm), Simplify ((a \<up> 2 + -1 * b \<up> 2) / (a \<up> 2 + -2 * a * b + b \<up> 2))),
  1663 (([1], Frm), (a \<up> 2 + -1 * b \<up> 2) / (a \<up> 2 + -2 * a * b + b \<up> 2)),
  1664 (([1], Res), (a \<up> 2 + -1 * b \<up> 2) / (a \<up> 2 + -2 * (a * b) + b \<up> 2)),
  1665 (([2,1], Frm), (a \<up> 2 + -1 * b \<up> 2) / (a \<up> 2 + -2 * (a * b) + b \<up> 2)),
  1666 (([2,1,1], Frm), (a \<up> 2 + -1 * b \<up> 2) / (a \<up> 2 + -2 * (a * b) + b \<up> 2)),
  1667 (([2,1,1], Res), (a \<up> 2 + -1 * (a * b) + a * b + -1 * b \<up> 2) /
  1668 (a \<up> 2 + -2 * (a * b) + 1 * b \<up> 2)),
  1669 (([2,1,2], Res), (a \<up> 2 + -1 * (a * b) + a * b + -1 * b \<up> 2) /
  1670 (a \<up> 2 + -2 * (a * b) + -1 \<up> 2 * b \<up> 2)),
  1671 (([2,1,3], Res), (a \<up> 2 + -1 * (a * b) + a * b + -1 * b \<up> 2) /
  1672 (a \<up> 2 + -2 * (a * b) + (-1 * b) \<up> 2)),
  1673 (([2,1,4], Res), (a * a + -1 * (a * b) + a * b + -1 * b \<up> 2) /
  1674 (a \<up> 2 + -2 * (a * b) + (-1 * b) \<up> 2)),
  1675 (([2,1,5], Res), (a * a + -1 * (a * b) + a * b + -1 * (b * b)) /
  1676 (a \<up> 2 + -2 * (a * b) + (-1 * b) \<up> 2)),
  1677 (([2,1,6], Res), (a * a + -1 * (a * b) + a * b + -1 * (b * b)) /
  1678 (a \<up> 2 + -1 * (2 * (a * b)) + (-1 * b) \<up> 2)),
  1679 (([2,1,7], Res), (a * a + a * (-1 * b) + (b * a + b * (-1 * b))) /
  1680 (a \<up> 2 + 2 * (a * (-1 * b)) + (-1 * b) \<up> 2)),
  1681 (([2,1,8], Res), (a * a + a * (-1 * b) + (b * a + b * (-1 * b))) /
  1682 (a \<up> 2 + 2 * a * (-1 * b) + (-1 * b) \<up> 2)),
  1683 (([2,1,9], Res), (a * (a + -1 * b) + (b * a + b * (-1 * b))) /
  1684 (a \<up> 2 + 2 * a * (-1 * b) + (-1 * b) \<up> 2)),
  1685 (([2,1,10], Res), (a * (a + -1 * b) + b * (a + -1 * b)) /
  1686 (a \<up> 2 + 2 * a * (-1 * b) + (-1 * b) \<up> 2)),
  1687 (([2,1,11], Res), (a + b) * (a + -1 * b) / (a \<up> 2 + 2 * a * (-1 * b) + (-1 * b) \<up> 2)),
  1688 (([2,1,12], Res), (a + b) * (a + -1 * b) / ((a + -1 * b) * (a + -1 * b))),
  1689 (([2,1,13], Res), (a + b) / (a + -1 * b)),
  1690 (([2,1], Res), (a + b) / (a + -1 * b)),
  1691 (([2], Res), (a + b) / (a + -1 * b)),
  1692 (([], Res), (a + b) / (a + -1 * b))] 
  1693 *)
  1694 val newnds = children (get_nd pt [2,1]) (*see "fun detailrls"*);
  1695 if length newnds = 13 then () else error "rational.sml: interSteps cancel_p rev_rew_p";
  1696 
  1697 val p = ([2,1,9],Res);
  1698 getTactic 1 p;
  1699 val (_, tac, _) = ME_Misc.pt_extract (pt, p);
  1700 case tac of SOME (Rewrite ("sym_distrib_left", _)) => ()
  1701 | _ => error "rational.sml: getTactic, sym_real_plus_binom_times1";
  1702 
  1703 
  1704 "-------- investigate rulesets for cancel_p ----------------------------------";
  1705 "-------- investigate rulesets for cancel_p ----------------------------------";
  1706 "-------- investigate rulesets for cancel_p ----------------------------------";
  1707 val thy = @{theory "Rational"};
  1708 val t = TermC.str2term "(a \<up> 2 + -1*b \<up> 2) / (a \<up> 2 + -2*a*b + b \<up> 2)";
  1709 val tt = TermC.str2term "(1 * a + 1 * b) * (1 * a + -1 * b)"(*numerator only*);
  1710 
  1711 "----- with rewrite_set_";
  1712 val SOME (tt',asm) = rewrite_set_ thy false make_polynomial tt;
  1713 if UnparseC.term tt'= "a \<up> 2 + -1 * b \<up> 2" then () else error "rls chancel_p 1";
  1714 val tt = TermC.str2term "((1 * a + -1 * b) * (1 * a + -1 * b))"(*denominator only*);
  1715 val SOME (tt',asm) = rewrite_set_ thy false make_polynomial tt;
  1716 if UnparseC.term tt' = "a \<up> 2 + -2 * a * b + b \<up> 2" then () else error "rls chancel_p 2";
  1717 
  1718 "----- with Derive.do_one; WN1130912 not investigated further, will be discontinued";
  1719 val SOME (tt, _) = factout_p_ thy t; 
  1720 if UnparseC.term tt = "(a + b) * (a + -1 * b) / ((a + -1 * b) * (a + -1 * b))"
  1721 then () else error "rls chancel_p 3";
  1722 UnparseC.term tt = "(1 * a + 1 * b) * (1 * a + -1 * b) / ((1 * a + -1 * b) * (1 * a + -1 * b))";
  1723 
  1724 "--- with simpler ruleset";
  1725 val {rules, rew_ord= (_, ro), ...} = Rule_Set.rep (assoc_rls "rev_rew_p");
  1726 val der = Derive.do_one thy Atools_erls rules ro NONE tt;
  1727 if length der = 12 then () else error "WN1130912 rls chancel_p 4";
  1728 (*default_print_depth 99;*) writeln (deriv2str der); (*default_print_depth 3;*)
  1729 
  1730 (*default_print_depth 99;*) map (UnparseC.term o #1) der; (*default_print_depth 3;*)
  1731 "...,(-1 * b \<up> 2 + a \<up> 2) / (-2 * (a * b) + a \<up> 2 + (-1 * b) \<up> 2) ]";
  1732 (*default_print_depth 99;*) map (Rule.to_string o #2) der; (*default_print_depth 3;*)
  1733 (*default_print_depth 99;*) map (UnparseC.term o #1 o #3) der; (*default_print_depth 3;*)
  1734 
  1735 val der = Derive.do_one thy Atools_erls rules ro NONE 
  1736 	(TermC.str2term "(1 * a + 1 * b) * (1 * a + -1 * b)");
  1737 (*default_print_depth 99;*) writeln (deriv2str der); (*default_print_depth 3;*)
  1738 
  1739 val {rules, rew_ord=(_,ro),...} = Rule_Set.rep (assoc_rls "rev_rew_p");
  1740 val der = Derive.do_one thy Atools_erls rules ro NONE 
  1741 	(TermC.str2term "(1 * a + -1 * b) * (1 * a + -1 * b)");
  1742 (*default_print_depth 99;*) writeln (deriv2str der); (*default_print_depth 3;*)
  1743 (*default_print_depth 99;*) map (UnparseC.term o #1) der; (*default_print_depth 3;*)
  1744 (*WN060829 ...postponed*)
  1745 
  1746 
  1747 "-------- fun eval_get_denominator -------------------------------------------";
  1748 "-------- fun eval_get_denominator -------------------------------------------";
  1749 "-------- fun eval_get_denominator -------------------------------------------";
  1750 val thy = @{theory Isac_Knowledge};
  1751 val t = Thm.term_of (the (TermC.parse thy "get_denominator ((a +x)/b)"));
  1752 val SOME (_, t') = eval_get_denominator "" 0 t thy;
  1753 if UnparseC.term t' = "get_denominator ((a + x) / b) = b"
  1754 then () else error "get_denominator ((a + x) / b) = b"
  1755 
  1756 
  1757 "-------- several errpats in complicated term --------------------------------";
  1758 "-------- several errpats in complicated term --------------------------------";
  1759 "-------- several errpats in complicated term --------------------------------";
  1760 (*WN12xxxx TODO: instead of Gabriella's example here (27.Jul.12) find a simpler one
  1761   WN130912: kept this test, although not clear what for*)
  1762 reset_states ();
  1763 CalcTree [(["Term ((5*b + 25)/(a^2 - b^2) * (a - b)/(5*b))", "normalform N"], 
  1764   ("Rational", ["rational", "simplification"], ["simplification", "of_rationals"]))];
  1765 Iterator 1;
  1766 moveActiveRoot 1;
  1767 autoCalculate 1 CompleteCalc;
  1768 val ((pt, p), _) = get_calc 1;
  1769 (*Test_Tool.show_pt pt;
  1770 [
  1771 (([], Frm), Simplify ((5 * b + 25) / (a \<up> 2 - b \<up> 2) * (a - b) / (5 * b))),
  1772 (([1], Frm), (5 * b + 25) / (a \<up> 2 - b \<up> 2) * (a - b) / (5 * b)),
  1773 (([1], Res), (5 * b + 25) / (a \<up> 2 + -1 * b \<up> 2) * (a + -1 * b) / (5 * b)),
  1774 (([2], Res), (5 * b + 25) * (a + -1 * b) / (a \<up> 2 + -1 * b \<up> 2) / (5 * b)),
  1775 (([3], Res), (25 * a + -25 * b + 5 * (a * b) + -5 * b \<up> 2) / (a \<up> 2 + -1 * b \<up> 2) /
  1776 (5 * b)),
  1777 (([4], Res), (25 + 5 * b) / (a + b) / (5 * b)),
  1778 (([5], Res), (25 + 5 * b) / ((a + b) * (5 * b))),
  1779 (([6], Res), (25 + 5 * b) / (5 * (a * b) + 5 * b \<up> 2)),
  1780 (([7], Res), (5 + b) / (a * b + b \<up> 2)),
  1781 (([], Res), (5 + b) / (a * b + b \<up> 2))] *)
  1782 
  1783 
  1784 "-------- WN1309xx non-terminating rls norm_Rational -------------------------";
  1785 "-------- WN1309xx non-terminating rls norm_Rational -------------------------";
  1786 "-------- WN1309xx non-terminating rls norm_Rational -------------------------";
  1787 (*------- Schalk I, p.70 Nr. 480b; a/b : c/d translated to a/b * d/c*)
  1788 val t = TermC.str2term 
  1789   ("((12*x*y / (9*x \<up> 2 - y \<up> 2))  /  (1 / (3*x - y) \<up> 2 - 1 / (3*x + y) \<up> 2))  *  " ^
  1790 	"((1/(x - 5*y) \<up> 2  -  1/(x + 5*y) \<up> 2)  /  (20*x*y / (x \<up> 2 - 25*y \<up> 2)))");
  1791 
  1792 (*1st factor separately simplified *)
  1793 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))";
  1794 val SOME (t', _) = rewrite_set_ thy false norm_Rational t; 
  1795 if UnparseC.term t' = "(-9 * x \<up> 2 + y \<up> 2) / -1" then () else error "Nr. 480b lhs changed";
  1796 (*2nd factor separately simplified *)
  1797 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)))";
  1798 val SOME (t',_) = rewrite_set_ thy false norm_Rational t; UnparseC.term t';
  1799 if UnparseC.term t' = "-1 / (-1 * x \<up> 2 + 25 * y \<up> 2)" then () else error "Nr. 480b rhs changed";
  1800 
  1801 "-------- Schalk I, p.70 Nr. 477a: terms are exploding ?!?";
  1802 val t = TermC.str2term ("b*y/(b - 2*y)/((b \<up> 2 - y \<up> 2)/(b+2*y))  /" ^
  1803 		 "(b \<up> 2*y + b*y \<up> 2) * (a+x) \<up> 2  /  ((b \<up> 2 - 4*y \<up> 2) * (a+2*x) \<up> 2)");
  1804 (*val SOME (t',_) = rewrite_set_ thy false norm_Rational t;
  1805 :
  1806 ###  rls: cancel_p on: (a \<up> 2 * (b * y) + 2 * (a * (b * (x * y))) + b * (x \<up> 2 * y)) /
  1807 (b + -2 * y) /
  1808 ((b \<up> 2 + -1 * y \<up> 2) / (b + 2 * y)) /
  1809 (b \<up> 2 * y + b * y \<up> 2) /
  1810 (a \<up> 2 * b \<up> 2 + -4 * (a \<up> 2 * y \<up> 2) + 4 * (a * (b \<up> 2 * x)) +
  1811  -16 * (a * (x * y \<up> 2)) +
  1812  4 * (b \<up> 2 * x \<up> 2) +
  1813  -16 * (x \<up> 2 * y \<up> 2)) 
  1814 exception Div raised
  1815 
  1816 BUT
  1817 val t = TermC.str2term 
  1818   ("(a \<up> 2 * (b * y) + 2 * (a * (b * (x * y))) + b * (x \<up> 2 * y)) /" ^
  1819   "(b + -2 * y) /" ^
  1820   "((b \<up> 2 + -1 * y \<up> 2) / (b + 2 * y)) /" ^
  1821   "(b \<up> 2 * y + b * y \<up> 2) /" ^
  1822   "(a \<up> 2 * b \<up> 2 + -4 * (a \<up> 2 * y \<up> 2) + 4 * (a * (b \<up> 2 * x)) +" ^
  1823   "-16 * (a * (x * y \<up> 2)) +" ^
  1824   "4 * (b \<up> 2 * x \<up> 2) +" ^
  1825   "-16 * (x \<up> 2 * y \<up> 2))");
  1826 NONE = cancel_p_ thy t;
  1827 *)
  1828 
  1829 (*------- Schalk I, p.70 Nr. 476b in 2003 this worked using 10 sec. *)
  1830 val t = TermC.str2term 
  1831   ("((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)    / " ^
  1832    "((a \<up> 2 + b \<up> 2) \<up> 2  /  (a + b) \<up> 2)");
  1833 (* Rewrite.trace_on := true;
  1834 rewrite_set_ thy false norm_Rational t;
  1835 :
  1836 ####  rls: cancel_p on: (2 * (a \<up> 7 * b) + 4 * (a \<up> 6 * b \<up> 2) + 6 * (a \<up> 5 * b \<up> 3) +
  1837  8 * (a \<up> 4 * b \<up> 4) +
  1838  6 * (a \<up> 3 * b \<up> 5) +
  1839  4 * (a \<up> 2 * b \<up> 6) +
  1840  2 * (a * b \<up> 7)) /
  1841 (2 * (a \<up> 9 * b) + 4 * (a \<up> 8 * b \<up> 2) +
  1842  2 * (2 * (a \<up> 7 * b \<up> 3)) +
  1843  4 * (a \<up> 6 * b \<up> 4) +
  1844  -4 * (a \<up> 4 * b \<up> 6) +
  1845  -4 * (a \<up> 3 * b \<up> 7) +
  1846  -4 * (a \<up> 2 * b \<up> 8) +
  1847  -2 * (a * b \<up> 9))
  1848 
  1849 if UnparseC.term t = "1 / (a \<up> 2 + -1 * b \<up> 2)" then ()
  1850 else error "rational.sml: diff.behav. in norm_Rational_mg 49";
  1851 *)
  1852 
  1853 "-------- Schalk I, p.70 Nr. 480a: terms are exploding ?!?";
  1854 val t = TermC.str2term ("(1/x + 1/y + 1/z)  /  (1/x - 1/y - 1/z)  /  " ^
  1855   "(2*x \<up> 2 / (x \<up> 2 - z \<up> 2) / (x / (x + z)  +  x / (x - z)))");
  1856 (* Rewrite.trace_on := true;
  1857 rewrite_set_ thy false norm_Rational t;
  1858 :
  1859 ####  rls: cancel_p on: (2 * (x \<up> 6 * (y \<up> 2 * z)) + 2 * (x \<up> 6 * (y * z \<up> 2)) +
  1860  2 * (x \<up> 5 * (y \<up> 2 * z \<up> 2)) +
  1861  -2 * (x \<up> 4 * (y \<up> 2 * z \<up> 3)) +
  1862  -2 * (x \<up> 4 * (y * z \<up> 4)) +
  1863  -2 * (x \<up> 3 * (y \<up> 2 * z \<up> 4))) /
  1864 (-2 * (x \<up> 6 * (y \<up> 2 * z)) + -2 * (x \<up> 6 * (y * z \<up> 2)) +
  1865  2 * (x \<up> 5 * (y \<up> 2 * z \<up> 2)) +
  1866  2 * (x \<up> 4 * (y \<up> 2 * z \<up> 3)) +
  1867  2 * (x \<up> 4 * (y * z \<up> 4)) +
  1868  -2 * (x \<up> 3 * (y \<up> 2 * z \<up> 4)))
  1869 *)
  1870 
  1871 "-------- Schalk I, p.60 Nr. 215d: terms are exploding, internal loop does not terminate";
  1872 val t = TermC.str2term "(a-b) \<up> 3 * (x+y) \<up> 4 / ((x+y) \<up> 2 * (a-b) \<up> 5)";
  1873 (* Kein Wunder, denn Z???ler und Nenner extra als Polynom dargestellt ergibt:
  1874 
  1875 val t = TermC.str2term "(a-b) \<up> 3 * (x+y) \<up> 4";
  1876 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1877 UnparseC.term t;
  1878 "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";
  1879 val t = TermC.str2term "((x+y) \<up> 2 * (a-b) \<up> 5)";
  1880 val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1881 UnparseC.term t;
  1882 "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";
  1883 
  1884 anscheinend macht dem Rechner das Krzen diese Bruches keinen Spass mehr ...*)
  1885 
  1886 "-------- Schalk I, p.70 Nr. 480b: terms are exploding, Rewrite.trace_on stops at";
  1887 val t = TermC.str2term ("((12*x*y/(9*x \<up> 2 - y \<up> 2))/" ^
  1888 		 "(1/(3*x - y) \<up> 2 - 1/(3*x + y) \<up> 2)) *" ^
  1889 		 "(1/(x - 5*y) \<up> 2 - 1/(x + 5*y) \<up> 2)/" ^
  1890 		 "(20*x*y/(x \<up> 2 - 25*y \<up> 2))");
  1891 (*val SOME (t, _) = rewrite_set_ thy false norm_Rational t;
  1892 :
  1893 ####  rls: cancel_p on: (19440 * (x \<up> 8 * y \<up> 2) + -490320 * (x \<up> 6 * y \<up> 4) +
  1894  108240 * (x \<up> 4 * y \<up> 6) +
  1895  -6000 * (x \<up> 2 * y \<up> 8)) /
  1896 (2160 * (x \<up> 8 * y \<up> 2) + -108240 * (x \<up> 6 * y \<up> 4) +
  1897  1362000 * (x \<up> 4 * y \<up> 6) +
  1898  -150000 * (x \<up> 2 * y \<up> 8))
  1899 *)
  1900