src/HOL/Library/positivstellensatz.ML
author wenzelm
Wed Feb 15 23:19:30 2012 +0100 (2012-02-15)
changeset 46497 89ccf66aa73d
parent 45654 cf10bde35973
child 46594 f11f332b964f
permissions -rw-r--r--
renamed Thm.capply to Thm.apply, and Thm.cabs to Thm.lambda in conformance with similar operations in structure Term and Logic;
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(*  Title:      HOL/Library/positivstellensatz.ML
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    Author:     Amine Chaieb, University of Cambridge
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A generic arithmetic prover based on Positivstellensatz certificates
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--- also implements Fourrier-Motzkin elimination as a special case
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Fourrier-Motzkin elimination.
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*)
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(* A functor for finite mappings based on Tables *)
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signature FUNC = 
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sig
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 include TABLE
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 val apply : 'a table -> key -> 'a
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 val applyd :'a table -> (key -> 'a) -> key -> 'a
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 val combine : ('a -> 'a -> 'a) -> ('a -> bool) -> 'a table -> 'a table -> 'a table
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 val dom : 'a table -> key list
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 val tryapplyd : 'a table -> key -> 'a -> 'a
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 val updatep : (key * 'a -> bool) -> key * 'a -> 'a table -> 'a table
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 val choose : 'a table -> key * 'a
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 val onefunc : key * 'a -> 'a table
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end;
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functor FuncFun(Key: KEY) : FUNC=
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struct
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structure Tab = Table(Key);
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open Tab;
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fun dom a = sort Key.ord (Tab.keys a);
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fun applyd f d x = case Tab.lookup f x of 
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   SOME y => y
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 | NONE => d x;
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fun apply f x = applyd f (fn _ => raise Tab.UNDEF x) x;
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fun tryapplyd f a d = applyd f (K d) a;
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fun updatep p (k,v) t = if p (k, v) then t else update (k,v) t
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fun combine f z a b = 
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 let
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  fun h (k,v) t = case Tab.lookup t k of
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     NONE => Tab.update (k,v) t
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   | SOME v' => let val w = f v v'
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     in if z w then Tab.delete k t else Tab.update (k,w) t end;
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  in Tab.fold h a b end;
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fun choose f = case Tab.min_key f of 
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   SOME k => (k, the (Tab.lookup f k))
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 | NONE => error "FuncFun.choose : Completely empty function"
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fun onefunc kv = update kv empty
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end;
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(* Some standard functors and utility functions for them *)
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structure FuncUtil =
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struct
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structure Intfunc = FuncFun(type key = int val ord = int_ord);
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structure Ratfunc = FuncFun(type key = Rat.rat val ord = Rat.ord);
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structure Intpairfunc = FuncFun(type key = int*int val ord = prod_ord int_ord int_ord);
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structure Symfunc = FuncFun(type key = string val ord = fast_string_ord);
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structure Termfunc = FuncFun(type key = term val ord = Term_Ord.fast_term_ord);
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val cterm_ord = Term_Ord.fast_term_ord o pairself term_of
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structure Ctermfunc = FuncFun(type key = cterm val ord = cterm_ord);
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type monomial = int Ctermfunc.table;
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val monomial_ord = list_ord (prod_ord cterm_ord int_ord) o pairself Ctermfunc.dest
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structure Monomialfunc = FuncFun(type key = monomial val ord = monomial_ord)
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type poly = Rat.rat Monomialfunc.table;
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(* The ordering so we can create canonical HOL polynomials.                  *)
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fun dest_monomial mon = sort (cterm_ord o pairself fst) (Ctermfunc.dest mon);
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fun monomial_order (m1,m2) =
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 if Ctermfunc.is_empty m2 then LESS 
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 else if Ctermfunc.is_empty m1 then GREATER 
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 else
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  let val mon1 = dest_monomial m1 
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      val mon2 = dest_monomial m2
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      val deg1 = fold (Integer.add o snd) mon1 0
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      val deg2 = fold (Integer.add o snd) mon2 0 
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  in if deg1 < deg2 then GREATER else if deg1 > deg2 then LESS
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     else list_ord (prod_ord cterm_ord int_ord) (mon1,mon2)
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  end;
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end
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(* positivstellensatz datatype and prover generation *)
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signature REAL_ARITH = 
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sig
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  datatype positivstellensatz =
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   Axiom_eq of int
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 | Axiom_le of int
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 | Axiom_lt of int
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 | Rational_eq of Rat.rat
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 | Rational_le of Rat.rat
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 | Rational_lt of Rat.rat
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 | Square of FuncUtil.poly
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 | Eqmul of FuncUtil.poly * positivstellensatz
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 | Sum of positivstellensatz * positivstellensatz
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 | Product of positivstellensatz * positivstellensatz;
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datatype pss_tree = Trivial | Cert of positivstellensatz | Branch of pss_tree * pss_tree
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datatype tree_choice = Left | Right
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type prover = tree_choice list -> 
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  (thm list * thm list * thm list -> positivstellensatz -> thm) ->
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  thm list * thm list * thm list -> thm * pss_tree
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type cert_conv = cterm -> thm * pss_tree
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val gen_gen_real_arith :
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  Proof.context -> (Rat.rat -> cterm) * conv * conv * conv *
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   conv * conv * conv * conv * conv * conv * prover -> cert_conv
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val real_linear_prover : (thm list * thm list * thm list -> positivstellensatz -> thm) ->
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  thm list * thm list * thm list -> thm * pss_tree
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val gen_real_arith : Proof.context ->
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  (Rat.rat -> cterm) * conv * conv * conv * conv * conv * conv * conv * prover -> cert_conv
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val gen_prover_real_arith : Proof.context -> prover -> cert_conv
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val is_ratconst : cterm -> bool
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val dest_ratconst : cterm -> Rat.rat
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val cterm_of_rat : Rat.rat -> cterm
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end
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structure RealArith : REAL_ARITH =
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struct
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 open Conv
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(* ------------------------------------------------------------------------- *)
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(* Data structure for Positivstellensatz refutations.                        *)
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(* ------------------------------------------------------------------------- *)
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datatype positivstellensatz =
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   Axiom_eq of int
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 | Axiom_le of int
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 | Axiom_lt of int
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 | Rational_eq of Rat.rat
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 | Rational_le of Rat.rat
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 | Rational_lt of Rat.rat
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 | Square of FuncUtil.poly
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 | Eqmul of FuncUtil.poly * positivstellensatz
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 | Sum of positivstellensatz * positivstellensatz
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 | Product of positivstellensatz * positivstellensatz;
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         (* Theorems used in the procedure *)
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datatype pss_tree = Trivial | Cert of positivstellensatz | Branch of pss_tree * pss_tree
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datatype tree_choice = Left | Right
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type prover = tree_choice list -> 
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  (thm list * thm list * thm list -> positivstellensatz -> thm) ->
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  thm list * thm list * thm list -> thm * pss_tree
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type cert_conv = cterm -> thm * pss_tree
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    (* Some useful derived rules *)
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fun deduct_antisym_rule tha thb = 
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    Thm.equal_intr (Thm.implies_intr (cprop_of thb) tha) 
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     (Thm.implies_intr (cprop_of tha) thb);
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fun prove_hyp tha thb =
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  if exists (curry op aconv (concl_of tha)) (Thm.hyps_of thb)  (* FIXME !? *)
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  then Thm.equal_elim (Thm.symmetric (deduct_antisym_rule tha thb)) tha else thb;
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val pth = @{lemma "(((x::real) < y) == (y - x > 0))" and "((x <= y) == (y - x >= 0))" and
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     "((x = y) == (x - y = 0))" and "((~(x < y)) == (x - y >= 0))" and
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     "((~(x <= y)) == (x - y > 0))" and "((~(x = y)) == (x - y > 0 | -(x - y) > 0))"
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  by (atomize (full), auto simp add: less_diff_eq le_diff_eq not_less)};
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val pth_final = @{lemma "(~p ==> False) ==> p" by blast}
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val pth_add = 
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  @{lemma "(x = (0::real) ==> y = 0 ==> x + y = 0 )" and "( x = 0 ==> y >= 0 ==> x + y >= 0)" and
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    "(x = 0 ==> y > 0 ==> x + y > 0)" and "(x >= 0 ==> y = 0 ==> x + y >= 0)" and
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    "(x >= 0 ==> y >= 0 ==> x + y >= 0)" and "(x >= 0 ==> y > 0 ==> x + y > 0)" and
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    "(x > 0 ==> y = 0 ==> x + y > 0)" and "(x > 0 ==> y >= 0 ==> x + y > 0)" and
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    "(x > 0 ==> y > 0 ==> x + y > 0)" by simp_all};
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val pth_mul = 
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  @{lemma "(x = (0::real) ==> y = 0 ==> x * y = 0)" and "(x = 0 ==> y >= 0 ==> x * y = 0)" and
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    "(x = 0 ==> y > 0 ==> x * y = 0)" and "(x >= 0 ==> y = 0 ==> x * y = 0)" and
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    "(x >= 0 ==> y >= 0 ==> x * y >= 0)" and "(x >= 0 ==> y > 0 ==> x * y >= 0)" and
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    "(x > 0 ==>  y = 0 ==> x * y = 0)" and "(x > 0 ==> y >= 0 ==> x * y >= 0)" and
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    "(x > 0 ==>  y > 0 ==> x * y > 0)"
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  by (auto intro: mult_mono[where a="0::real" and b="x" and d="y" and c="0", simplified]
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    mult_strict_mono[where b="x" and d="y" and a="0" and c="0", simplified])};
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val pth_emul = @{lemma "y = (0::real) ==> x * y = 0"  by simp};
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val pth_square = @{lemma "x * x >= (0::real)"  by simp};
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val weak_dnf_simps =
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  List.take (@{thms simp_thms}, 34) @
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    @{lemma "((P & (Q | R)) = ((P&Q) | (P&R)))" and "((Q | R) & P) = ((Q&P) | (R&P))" and
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      "(P & Q) = (Q & P)" and "((P | Q) = (Q | P))" by blast+};
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(*
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val nnfD_simps =
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  @{lemma "((~(P & Q)) = (~P | ~Q))" and "((~(P | Q)) = (~P & ~Q) )" and
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    "((P --> Q) = (~P | Q) )" and "((P = Q) = ((P & Q) | (~P & ~ Q)))" and
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    "((~(P = Q)) = ((P & ~ Q) | (~P & Q)) )" and "((~ ~(P)) = P)" by blast+};
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*)
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val choice_iff = @{lemma "(ALL x. EX y. P x y) = (EX f. ALL x. P x (f x))" by metis};
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val prenex_simps =
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  map (fn th => th RS sym)
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    ([@{thm "all_conj_distrib"}, @{thm "ex_disj_distrib"}] @
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      @{thms "HOL.all_simps"(1-4)} @ @{thms "ex_simps"(1-4)});
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val real_abs_thms1 = @{lemma
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  "((-1 * abs(x::real) >= r) = (-1 * x >= r & 1 * x >= r))" and
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  "((-1 * abs(x) + a >= r) = (a + -1 * x >= r & a + 1 * x >= r))" and
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  "((a + -1 * abs(x) >= r) = (a + -1 * x >= r & a + 1 * x >= r))" and
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  "((a + -1 * abs(x) + b >= r) = (a + -1 * x + b >= r & a + 1 * x + b >= r))" and
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  "((a + b + -1 * abs(x) >= r) = (a + b + -1 * x >= r & a + b + 1 * x >= r))" and
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  "((a + b + -1 * abs(x) + c >= r) = (a + b + -1 * x + c >= r & a + b + 1 * x + c >= r))" and
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  "((-1 * max x y >= r) = (-1 * x >= r & -1 * y >= r))" and
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  "((-1 * max x y + a >= r) = (a + -1 * x >= r & a + -1 * y >= r))" and
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  "((a + -1 * max x y >= r) = (a + -1 * x >= r & a + -1 * y >= r))" and
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  "((a + -1 * max x y + b >= r) = (a + -1 * x + b >= r & a + -1 * y  + b >= r))" and
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  "((a + b + -1 * max x y >= r) = (a + b + -1 * x >= r & a + b + -1 * y >= r))" and
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  "((a + b + -1 * max x y + c >= r) = (a + b + -1 * x + c >= r & a + b + -1 * y  + c >= r))" and
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  "((1 * min x y >= r) = (1 * x >= r & 1 * y >= r))" and
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  "((1 * min x y + a >= r) = (a + 1 * x >= r & a + 1 * y >= r))" and
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  "((a + 1 * min x y >= r) = (a + 1 * x >= r & a + 1 * y >= r))" and
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  "((a + 1 * min x y + b >= r) = (a + 1 * x + b >= r & a + 1 * y  + b >= r))" and
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  "((a + b + 1 * min x y >= r) = (a + b + 1 * x >= r & a + b + 1 * y >= r))" and
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  "((a + b + 1 * min x y + c >= r) = (a + b + 1 * x + c >= r & a + b + 1 * y  + c >= r))" and
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  "((min x y >= r) = (x >= r &  y >= r))" and
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  "((min x y + a >= r) = (a + x >= r & a + y >= r))" and
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  "((a + min x y >= r) = (a + x >= r & a + y >= r))" and
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  "((a + min x y + b >= r) = (a + x + b >= r & a + y  + b >= r))" and
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  "((a + b + min x y >= r) = (a + b + x >= r & a + b + y >= r))" and
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  "((a + b + min x y + c >= r) = (a + b + x + c >= r & a + b + y + c >= r))" and
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  "((-1 * abs(x) > r) = (-1 * x > r & 1 * x > r))" and
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  "((-1 * abs(x) + a > r) = (a + -1 * x > r & a + 1 * x > r))" and
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  "((a + -1 * abs(x) > r) = (a + -1 * x > r & a + 1 * x > r))" and
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  "((a + -1 * abs(x) + b > r) = (a + -1 * x + b > r & a + 1 * x + b > r))" and
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  "((a + b + -1 * abs(x) > r) = (a + b + -1 * x > r & a + b + 1 * x > r))" and
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  "((a + b + -1 * abs(x) + c > r) = (a + b + -1 * x + c > r & a + b + 1 * x + c > r))" and
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  "((-1 * max x y > r) = ((-1 * x > r) & -1 * y > r))" and
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  "((-1 * max x y + a > r) = (a + -1 * x > r & a + -1 * y > r))" and
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  "((a + -1 * max x y > r) = (a + -1 * x > r & a + -1 * y > r))" and
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  "((a + -1 * max x y + b > r) = (a + -1 * x + b > r & a + -1 * y  + b > r))" and
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  "((a + b + -1 * max x y > r) = (a + b + -1 * x > r & a + b + -1 * y > r))" and
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  "((a + b + -1 * max x y + c > r) = (a + b + -1 * x + c > r & a + b + -1 * y  + c > r))" and
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  "((min x y > r) = (x > r &  y > r))" and
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  "((min x y + a > r) = (a + x > r & a + y > r))" and
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  "((a + min x y > r) = (a + x > r & a + y > r))" and
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  "((a + min x y + b > r) = (a + x + b > r & a + y  + b > r))" and
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  "((a + b + min x y > r) = (a + b + x > r & a + b + y > r))" and
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  "((a + b + min x y + c > r) = (a + b + x + c > r & a + b + y + c > r))"
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  by auto};
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val abs_split' = @{lemma "P (abs (x::'a::linordered_idom)) == (x >= 0 & P x | x < 0 & P (-x))"
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  by (atomize (full)) (auto split add: abs_split)};
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val max_split = @{lemma "P (max x y) == ((x::'a::linorder) <= y & P y | x > y & P x)"
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  by (atomize (full)) (cases "x <= y", auto simp add: max_def)};
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val min_split = @{lemma "P (min x y) == ((x::'a::linorder) <= y & P x | x > y & P y)"
chaieb@31120
   272
  by (atomize (full)) (cases "x <= y", auto simp add: min_def)};
chaieb@31120
   273
chaieb@31120
   274
krauss@39920
   275
         (* Miscellaneous *)
chaieb@31120
   276
fun literals_conv bops uops cv = 
chaieb@31120
   277
 let fun h t =
chaieb@31120
   278
  case (term_of t) of 
chaieb@31120
   279
   b$_$_ => if member (op aconv) bops b then binop_conv h t else cv t
chaieb@31120
   280
 | u$_ => if member (op aconv) uops u then arg_conv h t else cv t
chaieb@31120
   281
 | _ => cv t
chaieb@31120
   282
 in h end;
chaieb@31120
   283
chaieb@31120
   284
fun cterm_of_rat x = 
chaieb@31120
   285
let val (a, b) = Rat.quotient_of_rat x
chaieb@31120
   286
in 
chaieb@31120
   287
 if b = 1 then Numeral.mk_cnumber @{ctyp "real"} a
wenzelm@46497
   288
  else Thm.apply (Thm.apply @{cterm "op / :: real => _"} 
chaieb@31120
   289
                   (Numeral.mk_cnumber @{ctyp "real"} a))
chaieb@31120
   290
        (Numeral.mk_cnumber @{ctyp "real"} b)
chaieb@31120
   291
end;
chaieb@31120
   292
chaieb@31120
   293
  fun dest_ratconst t = case term_of t of
chaieb@31120
   294
   Const(@{const_name divide}, _)$a$b => Rat.rat_of_quotient(HOLogic.dest_number a |> snd, HOLogic.dest_number b |> snd)
chaieb@31120
   295
 | _ => Rat.rat_of_int (HOLogic.dest_number (term_of t) |> snd)
chaieb@31120
   296
 fun is_ratconst t = can dest_ratconst t
chaieb@31120
   297
huffman@44454
   298
(*
chaieb@31120
   299
fun find_term p t = if p t then t else 
chaieb@31120
   300
 case t of
chaieb@31120
   301
  a$b => (find_term p a handle TERM _ => find_term p b)
chaieb@31120
   302
 | Abs (_,_,t') => find_term p t'
chaieb@31120
   303
 | _ => raise TERM ("find_term",[t]);
huffman@44454
   304
*)
chaieb@31120
   305
chaieb@31120
   306
fun find_cterm p t = if p t then t else 
chaieb@31120
   307
 case term_of t of
huffman@44454
   308
  _$_ => (find_cterm p (Thm.dest_fun t) handle CTERM _ => find_cterm p (Thm.dest_arg t))
huffman@44454
   309
 | Abs (_,_,_) => find_cterm p (Thm.dest_abs NONE t |> snd)
chaieb@31120
   310
 | _ => raise CTERM ("find_cterm",[t]);
chaieb@31120
   311
chaieb@31120
   312
    (* Some conversions-related stuff which has been forbidden entrance into Pure/conv.ML*)
chaieb@31120
   313
fun instantiate_cterm' ty tms = Drule.cterm_rule (Drule.instantiate' ty tms)
chaieb@31120
   314
fun is_comb t = case (term_of t) of _$_ => true | _ => false;
chaieb@31120
   315
chaieb@31120
   316
fun is_binop ct ct' = ct aconvc (Thm.dest_fun (Thm.dest_fun ct'))
chaieb@31120
   317
  handle CTERM _ => false;
chaieb@31120
   318
Philipp@32645
   319
Philipp@32645
   320
(* Map back polynomials to HOL.                         *)
Philipp@32645
   321
wenzelm@46497
   322
fun cterm_of_varpow x k = if k = 1 then x else Thm.apply (Thm.apply @{cterm "op ^ :: real => _"} x) 
Philipp@32828
   323
  (Numeral.mk_cnumber @{ctyp nat} k)
Philipp@32645
   324
Philipp@32645
   325
fun cterm_of_monomial m = 
Philipp@32829
   326
 if FuncUtil.Ctermfunc.is_empty m then @{cterm "1::real"} 
Philipp@32645
   327
 else 
Philipp@32645
   328
  let 
Philipp@32828
   329
   val m' = FuncUtil.dest_monomial m
Philipp@32645
   330
   val vps = fold_rev (fn (x,k) => cons (cterm_of_varpow x k)) m' [] 
wenzelm@46497
   331
  in foldr1 (fn (s, t) => Thm.apply (Thm.apply @{cterm "op * :: real => _"} s) t) vps
Philipp@32645
   332
  end
Philipp@32645
   333
Philipp@32829
   334
fun cterm_of_cmonomial (m,c) = if FuncUtil.Ctermfunc.is_empty m then cterm_of_rat c
Philipp@32645
   335
    else if c = Rat.one then cterm_of_monomial m
wenzelm@46497
   336
    else Thm.apply (Thm.apply @{cterm "op *::real => _"} (cterm_of_rat c)) (cterm_of_monomial m);
Philipp@32645
   337
Philipp@32645
   338
fun cterm_of_poly p = 
Philipp@32829
   339
 if FuncUtil.Monomialfunc.is_empty p then @{cterm "0::real"} 
Philipp@32645
   340
 else
Philipp@32645
   341
  let 
Philipp@32645
   342
   val cms = map cterm_of_cmonomial
Philipp@32829
   343
     (sort (prod_ord FuncUtil.monomial_order (K EQUAL)) (FuncUtil.Monomialfunc.dest p))
wenzelm@46497
   344
  in foldr1 (fn (t1, t2) => Thm.apply(Thm.apply @{cterm "op + :: real => _"} t1) t2) cms
Philipp@32645
   345
  end;
Philipp@32645
   346
chaieb@31120
   347
    (* A general real arithmetic prover *)
chaieb@31120
   348
chaieb@31120
   349
fun gen_gen_real_arith ctxt (mk_numeric,
chaieb@31120
   350
       numeric_eq_conv,numeric_ge_conv,numeric_gt_conv,
chaieb@31120
   351
       poly_conv,poly_neg_conv,poly_add_conv,poly_mul_conv,
chaieb@31120
   352
       absconv1,absconv2,prover) = 
chaieb@31120
   353
let
wenzelm@45654
   354
 val pre_ss = HOL_basic_ss addsimps
wenzelm@45654
   355
  @{thms simp_thms ex_simps all_simps not_all not_ex ex_disj_distrib all_conj_distrib if_bool_eq_disj}
chaieb@31120
   356
 val prenex_ss = HOL_basic_ss addsimps prenex_simps
chaieb@31120
   357
 val skolemize_ss = HOL_basic_ss addsimps [choice_iff]
chaieb@31120
   358
 val presimp_conv = Simplifier.rewrite (Simplifier.context ctxt pre_ss)
chaieb@31120
   359
 val prenex_conv = Simplifier.rewrite (Simplifier.context ctxt prenex_ss)
chaieb@31120
   360
 val skolemize_conv = Simplifier.rewrite (Simplifier.context ctxt skolemize_ss)
chaieb@31120
   361
 val weak_dnf_ss = HOL_basic_ss addsimps weak_dnf_simps
chaieb@31120
   362
 val weak_dnf_conv = Simplifier.rewrite (Simplifier.context ctxt weak_dnf_ss)
wenzelm@36945
   363
 fun eqT_elim th = Thm.equal_elim (Thm.symmetric th) @{thm TrueI}
chaieb@31120
   364
 fun oprconv cv ct = 
chaieb@31120
   365
  let val g = Thm.dest_fun2 ct
chaieb@31120
   366
  in if g aconvc @{cterm "op <= :: real => _"} 
chaieb@31120
   367
       orelse g aconvc @{cterm "op < :: real => _"} 
chaieb@31120
   368
     then arg_conv cv ct else arg1_conv cv ct
chaieb@31120
   369
  end
chaieb@31120
   370
chaieb@31120
   371
 fun real_ineq_conv th ct =
chaieb@31120
   372
  let
Philipp@32828
   373
   val th' = (Thm.instantiate (Thm.match (Thm.lhs_of th, ct)) th 
wenzelm@37117
   374
      handle Pattern.MATCH => raise CTERM ("real_ineq_conv", [ct]))
wenzelm@36945
   375
  in Thm.transitive th' (oprconv poly_conv (Thm.rhs_of th'))
chaieb@31120
   376
  end 
chaieb@31120
   377
  val [real_lt_conv, real_le_conv, real_eq_conv,
chaieb@31120
   378
       real_not_lt_conv, real_not_le_conv, _] =
chaieb@31120
   379
       map real_ineq_conv pth
chaieb@31120
   380
  fun match_mp_rule ths ths' = 
chaieb@31120
   381
   let
chaieb@31120
   382
     fun f ths ths' = case ths of [] => raise THM("match_mp_rule",0,ths)
chaieb@31120
   383
      | th::ths => (ths' MRS th handle THM _ => f ths ths')
chaieb@31120
   384
   in f ths ths' end
chaieb@31120
   385
  fun mul_rule th th' = fconv_rule (arg_conv (oprconv poly_mul_conv))
chaieb@31120
   386
         (match_mp_rule pth_mul [th, th'])
chaieb@31120
   387
  fun add_rule th th' = fconv_rule (arg_conv (oprconv poly_add_conv))
chaieb@31120
   388
         (match_mp_rule pth_add [th, th'])
chaieb@31120
   389
  fun emul_rule ct th = fconv_rule (arg_conv (oprconv poly_mul_conv)) 
chaieb@31120
   390
       (instantiate' [] [SOME ct] (th RS pth_emul)) 
chaieb@31120
   391
  fun square_rule t = fconv_rule (arg_conv (oprconv poly_conv))
chaieb@31120
   392
       (instantiate' [] [SOME t] pth_square)
chaieb@31120
   393
chaieb@31120
   394
  fun hol_of_positivstellensatz(eqs,les,lts) proof =
chaieb@31120
   395
   let 
chaieb@31120
   396
    fun translate prf = case prf of
chaieb@31120
   397
        Axiom_eq n => nth eqs n
chaieb@31120
   398
      | Axiom_le n => nth les n
chaieb@31120
   399
      | Axiom_lt n => nth lts n
wenzelm@46497
   400
      | Rational_eq x => eqT_elim(numeric_eq_conv(Thm.apply @{cterm Trueprop} 
wenzelm@46497
   401
                          (Thm.apply (Thm.apply @{cterm "op =::real => _"} (mk_numeric x)) 
chaieb@31120
   402
                               @{cterm "0::real"})))
wenzelm@46497
   403
      | Rational_le x => eqT_elim(numeric_ge_conv(Thm.apply @{cterm Trueprop} 
wenzelm@46497
   404
                          (Thm.apply (Thm.apply @{cterm "op <=::real => _"} 
chaieb@31120
   405
                                     @{cterm "0::real"}) (mk_numeric x))))
wenzelm@46497
   406
      | Rational_lt x => eqT_elim(numeric_gt_conv(Thm.apply @{cterm Trueprop} 
wenzelm@46497
   407
                      (Thm.apply (Thm.apply @{cterm "op <::real => _"} @{cterm "0::real"})
chaieb@31120
   408
                        (mk_numeric x))))
Philipp@32645
   409
      | Square pt => square_rule (cterm_of_poly pt)
Philipp@32645
   410
      | Eqmul(pt,p) => emul_rule (cterm_of_poly pt) (translate p)
chaieb@31120
   411
      | Sum(p1,p2) => add_rule (translate p1) (translate p2)
chaieb@31120
   412
      | Product(p1,p2) => mul_rule (translate p1) (translate p2)
chaieb@31120
   413
   in fconv_rule (first_conv [numeric_ge_conv, numeric_gt_conv, numeric_eq_conv, all_conv]) 
chaieb@31120
   414
          (translate proof)
chaieb@31120
   415
   end
chaieb@31120
   416
  
chaieb@31120
   417
  val init_conv = presimp_conv then_conv
chaieb@31120
   418
      nnf_conv then_conv skolemize_conv then_conv prenex_conv then_conv
chaieb@31120
   419
      weak_dnf_conv
chaieb@31120
   420
Philipp@32828
   421
  val concl = Thm.dest_arg o cprop_of
Philipp@32828
   422
  fun is_binop opr ct = (Thm.dest_fun2 ct aconvc opr handle CTERM _ => false)
chaieb@31120
   423
  val is_req = is_binop @{cterm "op =:: real => _"}
chaieb@31120
   424
  val is_ge = is_binop @{cterm "op <=:: real => _"}
chaieb@31120
   425
  val is_gt = is_binop @{cterm "op <:: real => _"}
haftmann@38795
   426
  val is_conj = is_binop @{cterm HOL.conj}
haftmann@38795
   427
  val is_disj = is_binop @{cterm HOL.disj}
chaieb@31120
   428
  fun conj_pair th = (th RS @{thm conjunct1}, th RS @{thm conjunct2})
chaieb@31120
   429
  fun disj_cases th th1 th2 = 
Philipp@32828
   430
   let val (p,q) = Thm.dest_binop (concl th)
chaieb@31120
   431
       val c = concl th1
chaieb@31120
   432
       val _ = if c aconvc (concl th2) then () else error "disj_cases : conclusions not alpha convertible"
wenzelm@36945
   433
   in Thm.implies_elim (Thm.implies_elim
wenzelm@36945
   434
          (Thm.implies_elim (instantiate' [] (map SOME [p,q,c]) @{thm disjE}) th)
wenzelm@46497
   435
          (Thm.implies_intr (Thm.apply @{cterm Trueprop} p) th1))
wenzelm@46497
   436
        (Thm.implies_intr (Thm.apply @{cterm Trueprop} q) th2)
chaieb@31120
   437
   end
Philipp@32645
   438
 fun overall cert_choice dun ths = case ths of
chaieb@31120
   439
  [] =>
chaieb@31120
   440
   let 
chaieb@31120
   441
    val (eq,ne) = List.partition (is_req o concl) dun
chaieb@31120
   442
     val (le,nl) = List.partition (is_ge o concl) ne
chaieb@31120
   443
     val lt = filter (is_gt o concl) nl 
Philipp@32645
   444
    in prover (rev cert_choice) hol_of_positivstellensatz (eq,le,lt) end
chaieb@31120
   445
 | th::oths =>
chaieb@31120
   446
   let 
chaieb@31120
   447
    val ct = concl th 
chaieb@31120
   448
   in 
chaieb@31120
   449
    if is_conj ct  then
chaieb@31120
   450
     let 
chaieb@31120
   451
      val (th1,th2) = conj_pair th in
Philipp@32645
   452
      overall cert_choice dun (th1::th2::oths) end
chaieb@31120
   453
    else if is_disj ct then
chaieb@31120
   454
      let 
wenzelm@46497
   455
       val (th1, cert1) = overall (Left::cert_choice) dun (Thm.assume (Thm.apply @{cterm Trueprop} (Thm.dest_arg1 ct))::oths)
wenzelm@46497
   456
       val (th2, cert2) = overall (Right::cert_choice) dun (Thm.assume (Thm.apply @{cterm Trueprop} (Thm.dest_arg ct))::oths)
Philipp@32645
   457
      in (disj_cases th th1 th2, Branch (cert1, cert2)) end
Philipp@32645
   458
   else overall cert_choice (th::dun) oths
chaieb@31120
   459
  end
Philipp@32828
   460
  fun dest_binary b ct = if is_binop b ct then Thm.dest_binop ct 
chaieb@31120
   461
                         else raise CTERM ("dest_binary",[b,ct])
chaieb@31120
   462
  val dest_eq = dest_binary @{cterm "op = :: real => _"}
chaieb@31120
   463
  val neq_th = nth pth 5
chaieb@31120
   464
  fun real_not_eq_conv ct = 
chaieb@31120
   465
   let 
Philipp@32828
   466
    val (l,r) = dest_eq (Thm.dest_arg ct)
Philipp@32828
   467
    val th = Thm.instantiate ([],[(@{cpat "?x::real"},l),(@{cpat "?y::real"},r)]) neq_th
Philipp@32828
   468
    val th_p = poly_conv(Thm.dest_arg(Thm.dest_arg1(Thm.rhs_of th)))
chaieb@31120
   469
    val th_x = Drule.arg_cong_rule @{cterm "uminus :: real => _"} th_p
chaieb@31120
   470
    val th_n = fconv_rule (arg_conv poly_neg_conv) th_x
haftmann@38795
   471
    val th' = Drule.binop_cong_rule @{cterm HOL.disj} 
wenzelm@46497
   472
     (Drule.arg_cong_rule (Thm.apply @{cterm "op <::real=>_"} @{cterm "0::real"}) th_p)
wenzelm@46497
   473
     (Drule.arg_cong_rule (Thm.apply @{cterm "op <::real=>_"} @{cterm "0::real"}) th_n)
wenzelm@36945
   474
    in Thm.transitive th th' 
chaieb@31120
   475
  end
chaieb@31120
   476
 fun equal_implies_1_rule PQ = 
chaieb@31120
   477
  let 
Philipp@32828
   478
   val P = Thm.lhs_of PQ
wenzelm@36945
   479
  in Thm.implies_intr P (Thm.equal_elim PQ (Thm.assume P))
chaieb@31120
   480
  end
chaieb@31120
   481
 (* FIXME!!! Copied from groebner.ml *)
chaieb@31120
   482
 val strip_exists =
chaieb@31120
   483
  let fun h (acc, t) =
chaieb@31120
   484
   case (term_of t) of
huffman@44454
   485
    Const(@{const_name Ex},_)$Abs(_,_,_) => h (Thm.dest_abs NONE (Thm.dest_arg t) |>> (fn v => v::acc))
chaieb@31120
   486
  | _ => (acc,t)
chaieb@31120
   487
  in fn t => h ([],t)
chaieb@31120
   488
  end
chaieb@31120
   489
  fun name_of x = case term_of x of
chaieb@31120
   490
   Free(s,_) => s
chaieb@31120
   491
 | Var ((s,_),_) => s
chaieb@31120
   492
 | _ => "x"
chaieb@31120
   493
wenzelm@36945
   494
  fun mk_forall x th = Drule.arg_cong_rule (instantiate_cterm' [SOME (ctyp_of_term x)] [] @{cpat "All :: (?'a => bool) => _" }) (Thm.abstract_rule (name_of x) x th)
chaieb@31120
   495
chaieb@31120
   496
  val specl = fold_rev (fn x => fn th => instantiate' [] [SOME x] (th RS spec));
chaieb@31120
   497
chaieb@31120
   498
 fun ext T = Drule.cterm_rule (instantiate' [SOME T] []) @{cpat Ex}
wenzelm@46497
   499
 fun mk_ex v t = Thm.apply (ext (ctyp_of_term v)) (Thm.lambda v t)
chaieb@31120
   500
chaieb@31120
   501
 fun choose v th th' = case concl_of th of 
haftmann@38558
   502
   @{term Trueprop} $ (Const(@{const_name Ex},_)$_) => 
chaieb@31120
   503
    let
chaieb@31120
   504
     val p = (funpow 2 Thm.dest_arg o cprop_of) th
chaieb@31120
   505
     val T = (hd o Thm.dest_ctyp o ctyp_of_term) p
chaieb@31120
   506
     val th0 = fconv_rule (Thm.beta_conversion true)
chaieb@31120
   507
         (instantiate' [SOME T] [SOME p, (SOME o Thm.dest_arg o cprop_of) th'] exE)
chaieb@31120
   508
     val pv = (Thm.rhs_of o Thm.beta_conversion true) 
wenzelm@46497
   509
           (Thm.apply @{cterm Trueprop} (Thm.apply p v))
wenzelm@36945
   510
     val th1 = Thm.forall_intr v (Thm.implies_intr pv th')
wenzelm@36945
   511
    in Thm.implies_elim (Thm.implies_elim th0 th) th1  end
chaieb@31120
   512
 | _ => raise THM ("choose",0,[th, th'])
chaieb@31120
   513
chaieb@31120
   514
  fun simple_choose v th = 
wenzelm@46497
   515
     choose v (Thm.assume ((Thm.apply @{cterm Trueprop} o mk_ex v) ((Thm.dest_arg o hd o #hyps o Thm.crep_thm) th))) th
chaieb@31120
   516
chaieb@31120
   517
 val strip_forall =
chaieb@31120
   518
  let fun h (acc, t) =
chaieb@31120
   519
   case (term_of t) of
huffman@44454
   520
    Const(@{const_name All},_)$Abs(_,_,_) => h (Thm.dest_abs NONE (Thm.dest_arg t) |>> (fn v => v::acc))
chaieb@31120
   521
  | _ => (acc,t)
chaieb@31120
   522
  in fn t => h ([],t)
chaieb@31120
   523
  end
chaieb@31120
   524
chaieb@31120
   525
 fun f ct =
chaieb@31120
   526
  let 
chaieb@31120
   527
   val nnf_norm_conv' = 
chaieb@31120
   528
     nnf_conv then_conv 
haftmann@38795
   529
     literals_conv [@{term HOL.conj}, @{term HOL.disj}] [] 
wenzelm@32843
   530
     (Conv.cache_conv 
chaieb@31120
   531
       (first_conv [real_lt_conv, real_le_conv, 
chaieb@31120
   532
                    real_eq_conv, real_not_lt_conv, 
chaieb@31120
   533
                    real_not_le_conv, real_not_eq_conv, all_conv]))
haftmann@38795
   534
  fun absremover ct = (literals_conv [@{term HOL.conj}, @{term HOL.disj}] [] 
chaieb@31120
   535
                  (try_conv (absconv1 then_conv binop_conv (arg_conv poly_conv))) then_conv 
chaieb@31120
   536
        try_conv (absconv2 then_conv nnf_norm_conv' then_conv binop_conv absremover)) ct
wenzelm@46497
   537
  val nct = Thm.apply @{cterm Trueprop} (Thm.apply @{cterm "Not"} ct)
chaieb@31120
   538
  val th0 = (init_conv then_conv arg_conv nnf_norm_conv') nct
Philipp@32828
   539
  val tm0 = Thm.dest_arg (Thm.rhs_of th0)
Philipp@32645
   540
  val (th, certificates) = if tm0 aconvc @{cterm False} then (equal_implies_1_rule th0, Trivial) else
chaieb@31120
   541
   let 
chaieb@31120
   542
    val (evs,bod) = strip_exists tm0
chaieb@31120
   543
    val (avs,ibod) = strip_forall bod
chaieb@31120
   544
    val th1 = Drule.arg_cong_rule @{cterm Trueprop} (fold mk_forall avs (absremover ibod))
wenzelm@36945
   545
    val (th2, certs) = overall [] [] [specl avs (Thm.assume (Thm.rhs_of th1))]
wenzelm@46497
   546
    val th3 = fold simple_choose evs (prove_hyp (Thm.equal_elim th1 (Thm.assume (Thm.apply @{cterm Trueprop} bod))) th2)
wenzelm@36945
   547
   in (Drule.implies_intr_hyps (prove_hyp (Thm.equal_elim th0 (Thm.assume nct)) th3), certs)
chaieb@31120
   548
   end
wenzelm@36945
   549
  in (Thm.implies_elim (instantiate' [] [SOME ct] pth_final) th, certificates)
chaieb@31120
   550
 end
chaieb@31120
   551
in f
chaieb@31120
   552
end;
chaieb@31120
   553
chaieb@31120
   554
(* A linear arithmetic prover *)
chaieb@31120
   555
local
Philipp@32828
   556
  val linear_add = FuncUtil.Ctermfunc.combine (curry op +/) (fn z => z =/ Rat.zero)
haftmann@39027
   557
  fun linear_cmul c = FuncUtil.Ctermfunc.map (fn _ => fn x => c */ x)
chaieb@31120
   558
  val one_tm = @{cterm "1::real"}
Philipp@32829
   559
  fun contradictory p (e,_) = ((FuncUtil.Ctermfunc.is_empty e) andalso not(p Rat.zero)) orelse
haftmann@33038
   560
     ((eq_set (op aconvc) (FuncUtil.Ctermfunc.dom e, [one_tm])) andalso
Philipp@32829
   561
       not(p(FuncUtil.Ctermfunc.apply e one_tm)))
chaieb@31120
   562
chaieb@31120
   563
  fun linear_ineqs vars (les,lts) = 
chaieb@31120
   564
   case find_first (contradictory (fn x => x >/ Rat.zero)) lts of
chaieb@31120
   565
    SOME r => r
chaieb@31120
   566
  | NONE => 
chaieb@31120
   567
   (case find_first (contradictory (fn x => x >/ Rat.zero)) les of
chaieb@31120
   568
     SOME r => r
chaieb@31120
   569
   | NONE => 
chaieb@31120
   570
     if null vars then error "linear_ineqs: no contradiction" else
chaieb@31120
   571
     let 
chaieb@31120
   572
      val ineqs = les @ lts
chaieb@31120
   573
      fun blowup v =
Philipp@32828
   574
       length(filter (fn (e,_) => FuncUtil.Ctermfunc.tryapplyd e v Rat.zero =/ Rat.zero) ineqs) +
Philipp@32828
   575
       length(filter (fn (e,_) => FuncUtil.Ctermfunc.tryapplyd e v Rat.zero >/ Rat.zero) ineqs) *
Philipp@32828
   576
       length(filter (fn (e,_) => FuncUtil.Ctermfunc.tryapplyd e v Rat.zero </ Rat.zero) ineqs)
chaieb@31120
   577
      val  v = fst(hd(sort (fn ((_,i),(_,j)) => int_ord (i,j))
chaieb@31120
   578
                 (map (fn v => (v,blowup v)) vars)))
chaieb@31120
   579
      fun addup (e1,p1) (e2,p2) acc =
chaieb@31120
   580
       let 
Philipp@32828
   581
        val c1 = FuncUtil.Ctermfunc.tryapplyd e1 v Rat.zero 
Philipp@32828
   582
        val c2 = FuncUtil.Ctermfunc.tryapplyd e2 v Rat.zero
chaieb@31120
   583
       in if c1 */ c2 >=/ Rat.zero then acc else
chaieb@31120
   584
        let 
chaieb@31120
   585
         val e1' = linear_cmul (Rat.abs c2) e1
chaieb@31120
   586
         val e2' = linear_cmul (Rat.abs c1) e2
chaieb@31120
   587
         val p1' = Product(Rational_lt(Rat.abs c2),p1)
chaieb@31120
   588
         val p2' = Product(Rational_lt(Rat.abs c1),p2)
chaieb@31120
   589
        in (linear_add e1' e2',Sum(p1',p2'))::acc
chaieb@31120
   590
        end
chaieb@31120
   591
       end
chaieb@31120
   592
      val (les0,les1) = 
Philipp@32828
   593
         List.partition (fn (e,_) => FuncUtil.Ctermfunc.tryapplyd e v Rat.zero =/ Rat.zero) les
chaieb@31120
   594
      val (lts0,lts1) = 
Philipp@32828
   595
         List.partition (fn (e,_) => FuncUtil.Ctermfunc.tryapplyd e v Rat.zero =/ Rat.zero) lts
chaieb@31120
   596
      val (lesp,lesn) = 
Philipp@32828
   597
         List.partition (fn (e,_) => FuncUtil.Ctermfunc.tryapplyd e v Rat.zero >/ Rat.zero) les1
chaieb@31120
   598
      val (ltsp,ltsn) = 
Philipp@32828
   599
         List.partition (fn (e,_) => FuncUtil.Ctermfunc.tryapplyd e v Rat.zero >/ Rat.zero) lts1
chaieb@31120
   600
      val les' = fold_rev (fn ep1 => fold_rev (addup ep1) lesp) lesn les0
chaieb@31120
   601
      val lts' = fold_rev (fn ep1 => fold_rev (addup ep1) (lesp@ltsp)) ltsn
chaieb@31120
   602
                      (fold_rev (fn ep1 => fold_rev (addup ep1) (lesn@ltsn)) ltsp lts0)
chaieb@31120
   603
     in linear_ineqs (remove (op aconvc) v vars) (les',lts')
chaieb@31120
   604
     end)
chaieb@31120
   605
chaieb@31120
   606
  fun linear_eqs(eqs,les,lts) = 
chaieb@31120
   607
   case find_first (contradictory (fn x => x =/ Rat.zero)) eqs of
chaieb@31120
   608
    SOME r => r
chaieb@31120
   609
  | NONE => (case eqs of 
chaieb@31120
   610
    [] => 
chaieb@31120
   611
     let val vars = remove (op aconvc) one_tm 
haftmann@33042
   612
           (fold_rev (union (op aconvc) o FuncUtil.Ctermfunc.dom o fst) (les@lts) []) 
chaieb@31120
   613
     in linear_ineqs vars (les,lts) end
chaieb@31120
   614
   | (e,p)::es => 
Philipp@32829
   615
     if FuncUtil.Ctermfunc.is_empty e then linear_eqs (es,les,lts) else
chaieb@31120
   616
     let 
Philipp@32829
   617
      val (x,c) = FuncUtil.Ctermfunc.choose (FuncUtil.Ctermfunc.delete_safe one_tm e)
chaieb@31120
   618
      fun xform (inp as (t,q)) =
Philipp@32828
   619
       let val d = FuncUtil.Ctermfunc.tryapplyd t x Rat.zero in
chaieb@31120
   620
        if d =/ Rat.zero then inp else
chaieb@31120
   621
        let 
chaieb@31120
   622
         val k = (Rat.neg d) */ Rat.abs c // c
chaieb@31120
   623
         val e' = linear_cmul k e
chaieb@31120
   624
         val t' = linear_cmul (Rat.abs c) t
Philipp@32829
   625
         val p' = Eqmul(FuncUtil.Monomialfunc.onefunc (FuncUtil.Ctermfunc.empty, k),p)
chaieb@31120
   626
         val q' = Product(Rational_lt(Rat.abs c),q) 
chaieb@31120
   627
        in (linear_add e' t',Sum(p',q')) 
chaieb@31120
   628
        end 
chaieb@31120
   629
      end
chaieb@31120
   630
     in linear_eqs(map xform es,map xform les,map xform lts)
chaieb@31120
   631
     end)
chaieb@31120
   632
chaieb@31120
   633
  fun linear_prover (eq,le,lt) = 
chaieb@31120
   634
   let 
haftmann@33063
   635
    val eqs = map_index (fn (n, p) => (p,Axiom_eq n)) eq
haftmann@33063
   636
    val les = map_index (fn (n, p) => (p,Axiom_le n)) le
haftmann@33063
   637
    val lts = map_index (fn (n, p) => (p,Axiom_lt n)) lt
chaieb@31120
   638
   in linear_eqs(eqs,les,lts)
chaieb@31120
   639
   end 
chaieb@31120
   640
  
chaieb@31120
   641
  fun lin_of_hol ct = 
Philipp@32829
   642
   if ct aconvc @{cterm "0::real"} then FuncUtil.Ctermfunc.empty
Philipp@32828
   643
   else if not (is_comb ct) then FuncUtil.Ctermfunc.onefunc (ct, Rat.one)
Philipp@32828
   644
   else if is_ratconst ct then FuncUtil.Ctermfunc.onefunc (one_tm, dest_ratconst ct)
chaieb@31120
   645
   else
chaieb@31120
   646
    let val (lop,r) = Thm.dest_comb ct 
Philipp@32828
   647
    in if not (is_comb lop) then FuncUtil.Ctermfunc.onefunc (ct, Rat.one)
chaieb@31120
   648
       else
chaieb@31120
   649
        let val (opr,l) = Thm.dest_comb lop 
chaieb@31120
   650
        in if opr aconvc @{cterm "op + :: real =>_"} 
chaieb@31120
   651
           then linear_add (lin_of_hol l) (lin_of_hol r)
chaieb@31120
   652
           else if opr aconvc @{cterm "op * :: real =>_"} 
Philipp@32828
   653
                   andalso is_ratconst l then FuncUtil.Ctermfunc.onefunc (r, dest_ratconst l)
Philipp@32828
   654
           else FuncUtil.Ctermfunc.onefunc (ct, Rat.one)
chaieb@31120
   655
        end
chaieb@31120
   656
    end
chaieb@31120
   657
chaieb@31120
   658
  fun is_alien ct = case term_of ct of 
chaieb@31120
   659
   Const(@{const_name "real"}, _)$ n => 
chaieb@31120
   660
     if can HOLogic.dest_number n then false else true
chaieb@31120
   661
  | _ => false
chaieb@31120
   662
in 
chaieb@31120
   663
fun real_linear_prover translator (eq,le,lt) = 
chaieb@31120
   664
 let 
Philipp@32828
   665
  val lhs = lin_of_hol o Thm.dest_arg1 o Thm.dest_arg o cprop_of
Philipp@32828
   666
  val rhs = lin_of_hol o Thm.dest_arg o Thm.dest_arg o cprop_of
chaieb@31120
   667
  val eq_pols = map lhs eq
chaieb@31120
   668
  val le_pols = map rhs le
chaieb@31120
   669
  val lt_pols = map rhs lt 
chaieb@31120
   670
  val aliens =  filter is_alien
haftmann@33042
   671
      (fold_rev (union (op aconvc) o FuncUtil.Ctermfunc.dom) 
chaieb@31120
   672
          (eq_pols @ le_pols @ lt_pols) [])
Philipp@32828
   673
  val le_pols' = le_pols @ map (fn v => FuncUtil.Ctermfunc.onefunc (v,Rat.one)) aliens
chaieb@31120
   674
  val (_,proof) = linear_prover (eq_pols,le_pols',lt_pols)
Philipp@32828
   675
  val le' = le @ map (fn a => instantiate' [] [SOME (Thm.dest_arg a)] @{thm real_of_nat_ge_zero}) aliens 
Philipp@32645
   676
 in ((translator (eq,le',lt) proof), Trivial)
chaieb@31120
   677
 end
chaieb@31120
   678
end;
chaieb@31120
   679
chaieb@31120
   680
(* A less general generic arithmetic prover dealing with abs,max and min*)
chaieb@31120
   681
chaieb@31120
   682
local
chaieb@31120
   683
 val absmaxmin_elim_ss1 = HOL_basic_ss addsimps real_abs_thms1
chaieb@31120
   684
 fun absmaxmin_elim_conv1 ctxt = 
chaieb@31120
   685
    Simplifier.rewrite (Simplifier.context ctxt absmaxmin_elim_ss1)
chaieb@31120
   686
chaieb@31120
   687
 val absmaxmin_elim_conv2 =
chaieb@31120
   688
  let 
chaieb@31120
   689
   val pth_abs = instantiate' [SOME @{ctyp real}] [] abs_split'
chaieb@31120
   690
   val pth_max = instantiate' [SOME @{ctyp real}] [] max_split
chaieb@31120
   691
   val pth_min = instantiate' [SOME @{ctyp real}] [] min_split
chaieb@31120
   692
   val abs_tm = @{cterm "abs :: real => _"}
chaieb@31120
   693
   val p_tm = @{cpat "?P :: real => bool"}
chaieb@31120
   694
   val x_tm = @{cpat "?x :: real"}
chaieb@31120
   695
   val y_tm = @{cpat "?y::real"}
chaieb@31120
   696
   val is_max = is_binop @{cterm "max :: real => _"}
chaieb@31120
   697
   val is_min = is_binop @{cterm "min :: real => _"} 
Philipp@32828
   698
   fun is_abs t = is_comb t andalso Thm.dest_fun t aconvc abs_tm
chaieb@31120
   699
   fun eliminate_construct p c tm =
chaieb@31120
   700
    let 
chaieb@31120
   701
     val t = find_cterm p tm
wenzelm@46497
   702
     val th0 = (Thm.symmetric o Thm.beta_conversion false) (Thm.apply (Thm.lambda t tm) t)
Philipp@32828
   703
     val (p,ax) = (Thm.dest_comb o Thm.rhs_of) th0
wenzelm@36945
   704
    in fconv_rule(arg_conv(binop_conv (arg_conv (Thm.beta_conversion false))))
wenzelm@36945
   705
               (Thm.transitive th0 (c p ax))
chaieb@31120
   706
   end
chaieb@31120
   707
chaieb@31120
   708
   val elim_abs = eliminate_construct is_abs
chaieb@31120
   709
    (fn p => fn ax => 
Philipp@32828
   710
       Thm.instantiate ([], [(p_tm,p), (x_tm, Thm.dest_arg ax)]) pth_abs)
chaieb@31120
   711
   val elim_max = eliminate_construct is_max
chaieb@31120
   712
    (fn p => fn ax => 
Philipp@32828
   713
      let val (ax,y) = Thm.dest_comb ax 
Philipp@32828
   714
      in  Thm.instantiate ([], [(p_tm,p), (x_tm, Thm.dest_arg ax), (y_tm,y)]) 
chaieb@31120
   715
      pth_max end)
chaieb@31120
   716
   val elim_min = eliminate_construct is_min
chaieb@31120
   717
    (fn p => fn ax => 
Philipp@32828
   718
      let val (ax,y) = Thm.dest_comb ax 
Philipp@32828
   719
      in  Thm.instantiate ([], [(p_tm,p), (x_tm, Thm.dest_arg ax), (y_tm,y)]) 
chaieb@31120
   720
      pth_min end)
chaieb@31120
   721
   in first_conv [elim_abs, elim_max, elim_min, all_conv]
chaieb@31120
   722
  end;
chaieb@31120
   723
in fun gen_real_arith ctxt (mkconst,eq,ge,gt,norm,neg,add,mul,prover) =
chaieb@31120
   724
        gen_gen_real_arith ctxt (mkconst,eq,ge,gt,norm,neg,add,mul,
chaieb@31120
   725
                       absmaxmin_elim_conv1 ctxt,absmaxmin_elim_conv2,prover)
chaieb@31120
   726
end;
chaieb@31120
   727
chaieb@31120
   728
(* An instance for reals*) 
chaieb@31120
   729
chaieb@31120
   730
fun gen_prover_real_arith ctxt prover = 
chaieb@31120
   731
 let
wenzelm@35408
   732
  fun simple_cterm_ord t u = Term_Ord.term_ord (term_of t, term_of u) = LESS
huffman@44454
   733
  val {add, mul, neg, pow = _, sub = _, main} = 
haftmann@36753
   734
     Semiring_Normalizer.semiring_normalizers_ord_wrapper ctxt
haftmann@36753
   735
      (the (Semiring_Normalizer.match ctxt @{cterm "(0::real) + 1"})) 
chaieb@31120
   736
     simple_cterm_ord
chaieb@31120
   737
in gen_real_arith ctxt
haftmann@36751
   738
   (cterm_of_rat, Numeral_Simprocs.field_comp_conv, Numeral_Simprocs.field_comp_conv, Numeral_Simprocs.field_comp_conv,
chaieb@31120
   739
    main,neg,add,mul, prover)
chaieb@31120
   740
end;
chaieb@31120
   741
chaieb@31120
   742
end