diff --git a/src/HOL/Library/Sum_of_Squares/positivstellensatz.ML b/src/HOL/Library/Sum_of_Squares/positivstellensatz.ML --- a/src/HOL/Library/Sum_of_Squares/positivstellensatz.ML +++ b/src/HOL/Library/Sum_of_Squares/positivstellensatz.ML @@ -1,779 +1,781 @@ (* Title: HOL/Library/positivstellensatz.ML Author: Amine Chaieb, University of Cambridge A generic arithmetic prover based on Positivstellensatz certificates --- also implements Fourier-Motzkin elimination as a special case Fourier-Motzkin elimination. *) (* A functor for finite mappings based on Tables *) signature FUNC = sig include TABLE val apply : 'a table -> key -> 'a val applyd :'a table -> (key -> 'a) -> key -> 'a val combine : ('a -> 'a -> 'a) -> ('a -> bool) -> 'a table -> 'a table -> 'a table val dom : 'a table -> key list val tryapplyd : 'a table -> key -> 'a -> 'a val updatep : (key * 'a -> bool) -> key * 'a -> 'a table -> 'a table val choose : 'a table -> key * 'a val onefunc : key * 'a -> 'a table end; functor FuncFun(Key: KEY) : FUNC = struct structure Tab = Table(Key); open Tab; fun dom a = sort Key.ord (Tab.keys a); fun applyd f d x = case Tab.lookup f x of SOME y => y | NONE => d x; fun apply f x = applyd f (fn _ => raise Tab.UNDEF x) x; fun tryapplyd f a d = applyd f (K d) a; fun updatep p (k,v) t = if p (k, v) then t else update (k,v) t fun combine f z a b = let fun h (k,v) t = case Tab.lookup t k of NONE => Tab.update (k,v) t | SOME v' => let val w = f v v' in if z w then Tab.delete k t else Tab.update (k,w) t end; in Tab.fold h a b end; fun choose f = (case Tab.min f of SOME entry => entry | NONE => error "FuncFun.choose : Completely empty function") fun onefunc kv = update kv empty end; (* Some standard functors and utility functions for them *) structure FuncUtil = struct structure Intfunc = FuncFun(type key = int val ord = int_ord); structure Ratfunc = FuncFun(type key = Rat.rat val ord = Rat.ord); structure Intpairfunc = FuncFun(type key = int*int val ord = prod_ord int_ord int_ord); structure Symfunc = FuncFun(type key = string val ord = fast_string_ord); structure Termfunc = FuncFun(type key = term val ord = Term_Ord.fast_term_ord); structure Ctermfunc = FuncFun(type key = cterm val ord = Thm.fast_term_ord); type monomial = int Ctermfunc.table; val monomial_ord = list_ord (prod_ord Thm.fast_term_ord int_ord) o apply2 Ctermfunc.dest structure Monomialfunc = FuncFun(type key = monomial val ord = monomial_ord) type poly = Rat.rat Monomialfunc.table; (* The ordering so we can create canonical HOL polynomials. *) fun dest_monomial mon = sort (Thm.fast_term_ord o apply2 fst) (Ctermfunc.dest mon); fun monomial_order (m1,m2) = if Ctermfunc.is_empty m2 then LESS else if Ctermfunc.is_empty m1 then GREATER else let val mon1 = dest_monomial m1 val mon2 = dest_monomial m2 val deg1 = fold (Integer.add o snd) mon1 0 val deg2 = fold (Integer.add o snd) mon2 0 in if deg1 < deg2 then GREATER else if deg1 > deg2 then LESS else list_ord (prod_ord Thm.fast_term_ord int_ord) (mon1,mon2) end; end (* positivstellensatz datatype and prover generation *) signature REAL_ARITH = sig datatype positivstellensatz = Axiom_eq of int | Axiom_le of int | Axiom_lt of int | Rational_eq of Rat.rat | Rational_le of Rat.rat | Rational_lt of Rat.rat | Square of FuncUtil.poly | Eqmul of FuncUtil.poly * positivstellensatz | Sum of positivstellensatz * positivstellensatz | Product of positivstellensatz * positivstellensatz; datatype pss_tree = Trivial | Cert of positivstellensatz | Branch of pss_tree * pss_tree datatype tree_choice = Left | Right type prover = tree_choice list -> (thm list * thm list * thm list -> positivstellensatz -> thm) -> thm list * thm list * thm list -> thm * pss_tree type cert_conv = cterm -> thm * pss_tree val gen_gen_real_arith : Proof.context -> (Rat.rat -> cterm) * conv * conv * conv * conv * conv * conv * conv * conv * conv * prover -> cert_conv val real_linear_prover : (thm list * thm list * thm list -> positivstellensatz -> thm) -> thm list * thm list * thm list -> thm * pss_tree val gen_real_arith : Proof.context -> (Rat.rat -> cterm) * conv * conv * conv * conv * conv * conv * conv * prover -> cert_conv val gen_prover_real_arith : Proof.context -> prover -> cert_conv val is_ratconst : cterm -> bool val dest_ratconst : cterm -> Rat.rat val cterm_of_rat : Rat.rat -> cterm end structure RealArith : REAL_ARITH = struct open Conv (* ------------------------------------------------------------------------- *) (* Data structure for Positivstellensatz refutations. *) (* ------------------------------------------------------------------------- *) datatype positivstellensatz = Axiom_eq of int | Axiom_le of int | Axiom_lt of int | Rational_eq of Rat.rat | Rational_le of Rat.rat | Rational_lt of Rat.rat | Square of FuncUtil.poly | Eqmul of FuncUtil.poly * positivstellensatz | Sum of positivstellensatz * positivstellensatz | Product of positivstellensatz * positivstellensatz; (* Theorems used in the procedure *) datatype pss_tree = Trivial | Cert of positivstellensatz | Branch of pss_tree * pss_tree datatype tree_choice = Left | Right type prover = tree_choice list -> (thm list * thm list * thm list -> positivstellensatz -> thm) -> thm list * thm list * thm list -> thm * pss_tree type cert_conv = cterm -> thm * pss_tree (* Some useful derived rules *) fun deduct_antisym_rule tha thb = Thm.equal_intr (Thm.implies_intr (Thm.cprop_of thb) tha) (Thm.implies_intr (Thm.cprop_of tha) thb); fun prove_hyp tha thb = if exists (curry op aconv (Thm.concl_of tha)) (Thm.hyps_of thb) (* FIXME !? *) then Thm.equal_elim (Thm.symmetric (deduct_antisym_rule tha thb)) tha else thb; val pth = @{lemma "(((x::real) < y) \ (y - x > 0))" and "((x \ y) \ (y - x \ 0))" and "((x = y) \ (x - y = 0))" and "((\(x < y)) \ (x - y \ 0))" and "((\(x \ y)) \ (x - y > 0))" and "((\(x = y)) \ (x - y > 0 \ -(x - y) > 0))" by (atomize (full), auto simp add: less_diff_eq le_diff_eq not_less)}; val pth_final = @{lemma "(\p \ False) \ p" by blast} val pth_add = @{lemma "(x = (0::real) \ y = 0 \ x + y = 0 )" and "( x = 0 \ y \ 0 \ x + y \ 0)" and "(x = 0 \ y > 0 \ x + y > 0)" and "(x \ 0 \ y = 0 \ x + y \ 0)" and "(x \ 0 \ y \ 0 \ x + y \ 0)" and "(x \ 0 \ y > 0 \ x + y > 0)" and "(x > 0 \ y = 0 \ x + y > 0)" and "(x > 0 \ y \ 0 \ x + y > 0)" and "(x > 0 \ y > 0 \ x + y > 0)" by simp_all}; val pth_mul = @{lemma "(x = (0::real) \ y = 0 \ x * y = 0)" and "(x = 0 \ y \ 0 \ x * y = 0)" and "(x = 0 \ y > 0 \ x * y = 0)" and "(x \ 0 \ y = 0 \ x * y = 0)" and "(x \ 0 \ y \ 0 \ x * y \ 0)" and "(x \ 0 \ y > 0 \ x * y \ 0)" and "(x > 0 \ y = 0 \ x * y = 0)" and "(x > 0 \ y \ 0 \ x * y \ 0)" and "(x > 0 \ y > 0 \ x * y > 0)" by (auto intro: mult_mono[where a="0::real" and b="x" and d="y" and c="0", simplified] mult_strict_mono[where b="x" and d="y" and a="0" and c="0", simplified])}; val pth_emul = @{lemma "y = (0::real) \ x * y = 0" by simp}; val pth_square = @{lemma "x * x \ (0::real)" by simp}; val weak_dnf_simps = List.take (@{thms simp_thms}, 34) @ @{lemma "((P \ (Q \ R)) = ((P\Q) \ (P\R)))" and "((Q \ R) \ P) = ((Q\P) \ (R\P))" and "(P \ Q) = (Q \ P)" and "((P \ Q) = (Q \ P))" by blast+}; (* val nnfD_simps = @{lemma "((~(P & Q)) = (~P | ~Q))" and "((~(P | Q)) = (~P & ~Q) )" and "((P --> Q) = (~P | Q) )" and "((P = Q) = ((P & Q) | (~P & ~ Q)))" and "((~(P = Q)) = ((P & ~ Q) | (~P & Q)) )" and "((~ ~(P)) = P)" by blast+}; *) val choice_iff = @{lemma "(\x. \y. P x y) = (\f. \x. P x (f x))" by metis}; val prenex_simps = map (fn th => th RS sym) ([@{thm "all_conj_distrib"}, @{thm "ex_disj_distrib"}] @ @{thms "HOL.all_simps"(1-4)} @ @{thms "ex_simps"(1-4)}); val real_abs_thms1 = @{lemma "((-1 * \x::real\ \ r) = (-1 * x \ r \ 1 * x \ r))" and "((-1 * \x\ + a \ r) = (a + -1 * x \ r \ a + 1 * x \ r))" and "((a + -1 * \x\ \ r) = (a + -1 * x \ r \ a + 1 * x \ r))" and "((a + -1 * \x\ + b \ r) = (a + -1 * x + b \ r \ a + 1 * x + b \ r))" and "((a + b + -1 * \x\ \ r) = (a + b + -1 * x \ r \ a + b + 1 * x \ r))" and "((a + b + -1 * \x\ + c \ r) = (a + b + -1 * x + c \ r \ a + b + 1 * x + c \ r))" and "((-1 * max x y \ r) = (-1 * x \ r \ -1 * y \ r))" and "((-1 * max x y + a \ r) = (a + -1 * x \ r \ a + -1 * y \ r))" and "((a + -1 * max x y \ r) = (a + -1 * x \ r \ a + -1 * y \ r))" and "((a + -1 * max x y + b \ r) = (a + -1 * x + b \ r \ a + -1 * y + b \ r))" and "((a + b + -1 * max x y \ r) = (a + b + -1 * x \ r \ a + b + -1 * y \ r))" and "((a + b + -1 * max x y + c \ r) = (a + b + -1 * x + c \ r \ a + b + -1 * y + c \ r))" and "((1 * min x y \ r) = (1 * x \ r \ 1 * y \ r))" and "((1 * min x y + a \ r) = (a + 1 * x \ r \ a + 1 * y \ r))" and "((a + 1 * min x y \ r) = (a + 1 * x \ r \ a + 1 * y \ r))" and "((a + 1 * min x y + b \ r) = (a + 1 * x + b \ r \ a + 1 * y + b \ r))" and "((a + b + 1 * min x y \ r) = (a + b + 1 * x \ r \ a + b + 1 * y \ r))" and "((a + b + 1 * min x y + c \ r) = (a + b + 1 * x + c \ r \ a + b + 1 * y + c \ r))" and "((min x y \ r) = (x \ r \ y \ r))" and "((min x y + a \ r) = (a + x \ r \ a + y \ r))" and "((a + min x y \ r) = (a + x \ r \ a + y \ r))" and "((a + min x y + b \ r) = (a + x + b \ r \ a + y + b \ r))" and "((a + b + min x y \ r) = (a + b + x \ r \ a + b + y \ r))" and "((a + b + min x y + c \ r) = (a + b + x + c \ r \ a + b + y + c \ r))" and "((-1 * \x\ > r) = (-1 * x > r \ 1 * x > r))" and "((-1 * \x\ + a > r) = (a + -1 * x > r \ a + 1 * x > r))" and "((a + -1 * \x\ > r) = (a + -1 * x > r \ a + 1 * x > r))" and "((a + -1 * \x\ + b > r) = (a + -1 * x + b > r \ a + 1 * x + b > r))" and "((a + b + -1 * \x\ > r) = (a + b + -1 * x > r \ a + b + 1 * x > r))" and "((a + b + -1 * \x\ + c > r) = (a + b + -1 * x + c > r \ a + b + 1 * x + c > r))" and "((-1 * max x y > r) = ((-1 * x > r) \ -1 * y > r))" and "((-1 * max x y + a > r) = (a + -1 * x > r \ a + -1 * y > r))" and "((a + -1 * max x y > r) = (a + -1 * x > r \ a + -1 * y > r))" and "((a + -1 * max x y + b > r) = (a + -1 * x + b > r \ a + -1 * y + b > r))" and "((a + b + -1 * max x y > r) = (a + b + -1 * x > r \ a + b + -1 * y > r))" and "((a + b + -1 * max x y + c > r) = (a + b + -1 * x + c > r \ a + b + -1 * y + c > r))" and "((min x y > r) = (x > r \ y > r))" and "((min x y + a > r) = (a + x > r \ a + y > r))" and "((a + min x y > r) = (a + x > r \ a + y > r))" and "((a + min x y + b > r) = (a + x + b > r \ a + y + b > r))" and "((a + b + min x y > r) = (a + b + x > r \ a + b + y > r))" and "((a + b + min x y + c > r) = (a + b + x + c > r \ a + b + y + c > r))" by auto}; val abs_split' = @{lemma "P \x::'a::linordered_idom\ == (x \ 0 \ P x \ x < 0 \ P (-x))" by (atomize (full)) (auto split: abs_split)}; val max_split = @{lemma "P (max x y) \ ((x::'a::linorder) \ y \ P y \ x > y \ P x)" by (atomize (full)) (cases "x \ y", auto simp add: max_def)}; val min_split = @{lemma "P (min x y) \ ((x::'a::linorder) \ y \ P x \ x > y \ P y)" by (atomize (full)) (cases "x \ y", auto simp add: min_def)}; (* Miscellaneous *) fun literals_conv bops uops cv = let fun h t = (case Thm.term_of t of b$_$_ => if member (op aconv) bops b then binop_conv h t else cv t | u$_ => if member (op aconv) uops u then arg_conv h t else cv t | _ => cv t) in h end; fun cterm_of_rat x = let val (a, b) = Rat.dest x in if b = 1 then Numeral.mk_cnumber \<^ctyp>\real\ a - else Thm.apply (Thm.apply \<^cterm>\(/) :: real \ _\ - (Numeral.mk_cnumber \<^ctyp>\real\ a)) - (Numeral.mk_cnumber \<^ctyp>\real\ b) + else + \<^instantiate>\ + a = \Numeral.mk_cnumber \<^ctyp>\real\ a\ and + b = \Numeral.mk_cnumber \<^ctyp>\real\ b\ + in cterm \a / b\ for a b :: real\ end; fun dest_ratconst t = case Thm.term_of t of - Const(\<^const_name>\divide\, _)$a$b => Rat.make(HOLogic.dest_number a |> snd, HOLogic.dest_number b |> snd) + \<^Const_>\divide _ for a b\ => Rat.make(HOLogic.dest_number a |> snd, HOLogic.dest_number b |> snd) | _ => Rat.of_int (HOLogic.dest_number (Thm.term_of t) |> snd) fun is_ratconst t = can dest_ratconst t (* fun find_term p t = if p t then t else case t of a$b => (find_term p a handle TERM _ => find_term p b) | Abs (_,_,t') => find_term p t' | _ => raise TERM ("find_term",[t]); *) fun find_cterm p t = if p t then t else case Thm.term_of t of _$_ => (find_cterm p (Thm.dest_fun t) handle CTERM _ => find_cterm p (Thm.dest_arg t)) | Abs (_,_,_) => find_cterm p (Thm.dest_abs_global t |> snd) | _ => raise CTERM ("find_cterm",[t]); fun is_comb t = (case Thm.term_of t of _ $ _ => true | _ => false); fun is_binop ct ct' = ct aconvc (Thm.dest_fun (Thm.dest_fun ct')) handle CTERM _ => false; (* Map back polynomials to HOL. *) -fun cterm_of_varpow x k = if k = 1 then x else Thm.apply (Thm.apply \<^cterm>\(^) :: real \ _\ x) - (Numeral.mk_cnumber \<^ctyp>\nat\ k) +fun cterm_of_varpow x k = + if k = 1 then x + else \<^instantiate>\x and k = \Numeral.mk_cnumber \<^ctyp>\nat\ k\ in cterm "x ^ k" for x :: real\ fun cterm_of_monomial m = if FuncUtil.Ctermfunc.is_empty m then \<^cterm>\1::real\ else let val m' = FuncUtil.dest_monomial m val vps = fold_rev (fn (x,k) => cons (cterm_of_varpow x k)) m' [] - in foldr1 (fn (s, t) => Thm.apply (Thm.apply \<^cterm>\(*) :: real \ _\ s) t) vps + in foldr1 (fn (s, t) => \<^instantiate>\s and t in cterm "s * t" for s t :: real\) vps end fun cterm_of_cmonomial (m,c) = if FuncUtil.Ctermfunc.is_empty m then cterm_of_rat c else if c = @1 then cterm_of_monomial m - else Thm.apply (Thm.apply \<^cterm>\(*)::real \ _\ (cterm_of_rat c)) (cterm_of_monomial m); + else \<^instantiate>\x = \cterm_of_rat c\ and y = \cterm_of_monomial m\ in cterm "x * y" for x y :: real\; fun cterm_of_poly p = if FuncUtil.Monomialfunc.is_empty p then \<^cterm>\0::real\ else let val cms = map cterm_of_cmonomial (sort (prod_ord FuncUtil.monomial_order (K EQUAL)) (FuncUtil.Monomialfunc.dest p)) - in foldr1 (fn (t1, t2) => Thm.apply(Thm.apply \<^cterm>\(+) :: real \ _\ t1) t2) cms + in foldr1 (fn (t1, t2) => \<^instantiate>\t1 and t2 in cterm "t1 + t2" for t1 t2 :: real\) cms end; (* A general real arithmetic prover *) fun gen_gen_real_arith ctxt (mk_numeric, numeric_eq_conv,numeric_ge_conv,numeric_gt_conv, poly_conv,poly_neg_conv,poly_add_conv,poly_mul_conv, absconv1,absconv2,prover) = let val pre_ss = put_simpset HOL_basic_ss ctxt addsimps @{thms simp_thms ex_simps all_simps not_all not_ex ex_disj_distrib all_conj_distrib if_bool_eq_disj} val prenex_ss = put_simpset HOL_basic_ss ctxt addsimps prenex_simps val skolemize_ss = put_simpset HOL_basic_ss ctxt addsimps [choice_iff] val presimp_conv = Simplifier.rewrite pre_ss val prenex_conv = Simplifier.rewrite prenex_ss val skolemize_conv = Simplifier.rewrite skolemize_ss val weak_dnf_ss = put_simpset HOL_basic_ss ctxt addsimps weak_dnf_simps val weak_dnf_conv = Simplifier.rewrite weak_dnf_ss fun eqT_elim th = Thm.equal_elim (Thm.symmetric th) @{thm TrueI} fun oprconv cv ct = let val g = Thm.dest_fun2 ct in if g aconvc \<^cterm>\(\) :: real \ _\ orelse g aconvc \<^cterm>\(<) :: real \ _\ then arg_conv cv ct else arg1_conv cv ct end fun real_ineq_conv th ct = let val th' = (Thm.instantiate (Thm.match (Thm.lhs_of th, ct)) th handle Pattern.MATCH => raise CTERM ("real_ineq_conv", [ct])) in Thm.transitive th' (oprconv poly_conv (Thm.rhs_of th')) end val [real_lt_conv, real_le_conv, real_eq_conv, real_not_lt_conv, real_not_le_conv, _] = map real_ineq_conv pth fun match_mp_rule ths ths' = let fun f ths ths' = case ths of [] => raise THM("match_mp_rule",0,ths) | th::ths => (ths' MRS th handle THM _ => f ths ths') in f ths ths' end fun mul_rule th th' = fconv_rule (arg_conv (oprconv poly_mul_conv)) (match_mp_rule pth_mul [th, th']) fun add_rule th th' = fconv_rule (arg_conv (oprconv poly_add_conv)) (match_mp_rule pth_add [th, th']) fun emul_rule ct th = fconv_rule (arg_conv (oprconv poly_mul_conv)) (Thm.instantiate' [] [SOME ct] (th RS pth_emul)) fun square_rule t = fconv_rule (arg_conv (oprconv poly_conv)) (Thm.instantiate' [] [SOME t] pth_square) fun hol_of_positivstellensatz(eqs,les,lts) proof = let fun translate prf = case prf of Axiom_eq n => nth eqs n | Axiom_le n => nth les n | Axiom_lt n => nth lts n - | Rational_eq x => eqT_elim(numeric_eq_conv(Thm.apply \<^cterm>\Trueprop\ - (Thm.apply (Thm.apply \<^cterm>\(=)::real \ _\ (mk_numeric x)) - \<^cterm>\0::real\))) - | Rational_le x => eqT_elim(numeric_ge_conv(Thm.apply \<^cterm>\Trueprop\ - (Thm.apply (Thm.apply \<^cterm>\(\)::real \ _\ - \<^cterm>\0::real\) (mk_numeric x)))) - | Rational_lt x => eqT_elim(numeric_gt_conv(Thm.apply \<^cterm>\Trueprop\ - (Thm.apply (Thm.apply \<^cterm>\(<)::real \ _\ \<^cterm>\0::real\) - (mk_numeric x)))) + | Rational_eq x => + eqT_elim (numeric_eq_conv + \<^instantiate>\x = \mk_numeric x\ in cprop "x = 0" for x :: real\) + | Rational_le x => + eqT_elim (numeric_ge_conv + \<^instantiate>\x = \mk_numeric x\ in cprop "x \ 0" for x :: real\) + | Rational_lt x => + eqT_elim (numeric_gt_conv + \<^instantiate>\x = \mk_numeric x\ in cprop "x > 0" for x :: real\) | Square pt => square_rule (cterm_of_poly pt) | Eqmul(pt,p) => emul_rule (cterm_of_poly pt) (translate p) | Sum(p1,p2) => add_rule (translate p1) (translate p2) | Product(p1,p2) => mul_rule (translate p1) (translate p2) in fconv_rule (first_conv [numeric_ge_conv, numeric_gt_conv, numeric_eq_conv, all_conv]) (translate proof) end val init_conv = presimp_conv then_conv nnf_conv ctxt then_conv skolemize_conv then_conv prenex_conv then_conv weak_dnf_conv val concl = Thm.dest_arg o Thm.cprop_of fun is_binop opr ct = (Thm.dest_fun2 ct aconvc opr handle CTERM _ => false) val is_req = is_binop \<^cterm>\(=):: real \ _\ val is_ge = is_binop \<^cterm>\(\):: real \ _\ val is_gt = is_binop \<^cterm>\(<):: real \ _\ val is_conj = is_binop \<^cterm>\HOL.conj\ val is_disj = is_binop \<^cterm>\HOL.disj\ fun conj_pair th = (th RS @{thm conjunct1}, th RS @{thm conjunct2}) fun disj_cases th th1 th2 = let val (p,q) = Thm.dest_binop (concl th) val c = concl th1 val _ = if c aconvc (concl th2) then () else error "disj_cases : conclusions not alpha convertible" in Thm.implies_elim (Thm.implies_elim (Thm.implies_elim (Thm.instantiate' [] (map SOME [p,q,c]) @{thm disjE}) th) - (Thm.implies_intr (Thm.apply \<^cterm>\Trueprop\ p) th1)) - (Thm.implies_intr (Thm.apply \<^cterm>\Trueprop\ q) th2) + (Thm.implies_intr \<^instantiate>\p in cprop p\ th1)) + (Thm.implies_intr \<^instantiate>\q in cprop q\ th2) end fun overall cert_choice dun ths = case ths of [] => let val (eq,ne) = List.partition (is_req o concl) dun val (le,nl) = List.partition (is_ge o concl) ne val lt = filter (is_gt o concl) nl in prover (rev cert_choice) hol_of_positivstellensatz (eq,le,lt) end | th::oths => let val ct = concl th in if is_conj ct then let val (th1,th2) = conj_pair th in overall cert_choice dun (th1::th2::oths) end else if is_disj ct then let val (th1, cert1) = overall (Left::cert_choice) dun (Thm.assume (Thm.apply \<^cterm>\Trueprop\ (Thm.dest_arg1 ct))::oths) val (th2, cert2) = overall (Right::cert_choice) dun (Thm.assume (Thm.apply \<^cterm>\Trueprop\ (Thm.dest_arg ct))::oths) in (disj_cases th th1 th2, Branch (cert1, cert2)) end else overall cert_choice (th::dun) oths end fun dest_binary b ct = if is_binop b ct then Thm.dest_binop ct else raise CTERM ("dest_binary",[b,ct]) val dest_eq = dest_binary \<^cterm>\(=) :: real \ _\ val neq_th = nth pth 5 fun real_not_eq_conv ct = let val (l,r) = dest_eq (Thm.dest_arg ct) val th = Thm.instantiate (TVars.empty, Vars.make [(\<^var>\?x::real\,l),(\<^var>\?y::real\,r)]) neq_th val th_p = poly_conv(Thm.dest_arg(Thm.dest_arg1(Thm.rhs_of th))) val th_x = Drule.arg_cong_rule \<^cterm>\uminus :: real \ _\ th_p val th_n = fconv_rule (arg_conv poly_neg_conv) th_x val th' = Drule.binop_cong_rule \<^cterm>\HOL.disj\ - (Drule.arg_cong_rule (Thm.apply \<^cterm>\(<)::real \ _\ \<^cterm>\0::real\) th_p) - (Drule.arg_cong_rule (Thm.apply \<^cterm>\(<)::real \ _\ \<^cterm>\0::real\) th_n) + (Drule.arg_cong_rule \<^cterm>\(<) (0::real)\ th_p) + (Drule.arg_cong_rule \<^cterm>\(<) (0::real)\ th_n) in Thm.transitive th th' end fun equal_implies_1_rule PQ = let val P = Thm.lhs_of PQ in Thm.implies_intr P (Thm.equal_elim PQ (Thm.assume P)) end (*FIXME!!! Copied from groebner.ml*) val strip_exists = let fun h (acc, t) = case Thm.term_of t of - Const(\<^const_name>\Ex\,_)$Abs(_,_,_) => + \<^Const_>\Ex _ for \Abs _\\ => h (Thm.dest_abs_global (Thm.dest_arg t) |>> (fn v => v::acc)) | _ => (acc,t) in fn t => h ([],t) end fun name_of x = case Thm.term_of x of Free(s,_) => s | Var ((s,_),_) => s | _ => "x" fun mk_forall x th = let - val T = Thm.typ_of_cterm x - val all = Thm.cterm_of ctxt (Const (\<^const_name>\All\, (T --> \<^typ>\bool\) --> \<^typ>\bool\)) + val T = Thm.ctyp_of_cterm x + val all = \<^instantiate>\'a = T in cterm All\ in Drule.arg_cong_rule all (Thm.abstract_rule (name_of x) x th) end val specl = fold_rev (fn x => fn th => Thm.instantiate' [] [SOME x] (th RS spec)); - fun ext T = Thm.cterm_of ctxt (Const (\<^const_name>\Ex\, (T --> \<^typ>\bool\) --> \<^typ>\bool\)) - fun mk_ex v t = Thm.apply (ext (Thm.typ_of_cterm v)) (Thm.lambda v t) + fun mk_ex v t = + \<^instantiate>\'a = \Thm.ctyp_of_cterm v\ and P = \Thm.lambda v t\ + in cprop "Ex P" for P :: "'a \ bool"\ fun choose v th th' = case Thm.concl_of th of - \<^term>\Trueprop\ $ (Const(\<^const_name>\Ex\,_)$_) => - let - val p = (funpow 2 Thm.dest_arg o Thm.cprop_of) th - val T = Thm.dest_ctyp0 (Thm.ctyp_of_cterm p) - val th0 = fconv_rule (Thm.beta_conversion true) - (Thm.instantiate' [SOME T] [SOME p, (SOME o Thm.dest_arg o Thm.cprop_of) th'] exE) - val pv = (Thm.rhs_of o Thm.beta_conversion true) - (Thm.apply \<^cterm>\Trueprop\ (Thm.apply p v)) - val th1 = Thm.forall_intr v (Thm.implies_intr pv th') - in Thm.implies_elim (Thm.implies_elim th0 th) th1 end + \<^Const_>\Trueprop for \<^Const_>\Ex _ for _\\ => + let + val p = (funpow 2 Thm.dest_arg o Thm.cprop_of) th + val T = Thm.dest_ctyp0 (Thm.ctyp_of_cterm p) + val th0 = fconv_rule (Thm.beta_conversion true) + (Thm.instantiate' [SOME T] [SOME p, (SOME o Thm.dest_arg o Thm.cprop_of) th'] exE) + val pv = (Thm.rhs_of o Thm.beta_conversion true) + (Thm.apply \<^cterm>\Trueprop\ (Thm.apply p v)) + val th1 = Thm.forall_intr v (Thm.implies_intr pv th') + in Thm.implies_elim (Thm.implies_elim th0 th) th1 end | _ => raise THM ("choose",0,[th, th']) fun simple_choose v th = - choose v - (Thm.assume - ((Thm.apply \<^cterm>\Trueprop\ o mk_ex v) (Thm.dest_arg (hd (Thm.chyps_of th))))) th + choose v (Thm.assume (mk_ex v (Thm.dest_arg (hd (Thm.chyps_of th))))) th val strip_forall = let fun h (acc, t) = case Thm.term_of t of - Const(\<^const_name>\All\,_)$Abs(_,_,_) => + \<^Const_>\All _ for \Abs _\\ => h (Thm.dest_abs_global (Thm.dest_arg t) |>> (fn v => v::acc)) | _ => (acc,t) in fn t => h ([],t) end fun f ct = let val nnf_norm_conv' = nnf_conv ctxt then_conv literals_conv [\<^term>\HOL.conj\, \<^term>\HOL.disj\] [] (Conv.cache_conv (first_conv [real_lt_conv, real_le_conv, real_eq_conv, real_not_lt_conv, real_not_le_conv, real_not_eq_conv, all_conv])) fun absremover ct = (literals_conv [\<^term>\HOL.conj\, \<^term>\HOL.disj\] [] (try_conv (absconv1 then_conv binop_conv (arg_conv poly_conv))) then_conv try_conv (absconv2 then_conv nnf_norm_conv' then_conv binop_conv absremover)) ct - val nct = Thm.apply \<^cterm>\Trueprop\ (Thm.apply \<^cterm>\Not\ ct) + val nct = \<^instantiate>\ct in cprop "\ ct"\ val th0 = (init_conv then_conv arg_conv nnf_norm_conv') nct val tm0 = Thm.dest_arg (Thm.rhs_of th0) val (th, certificates) = if tm0 aconvc \<^cterm>\False\ then (equal_implies_1_rule th0, Trivial) else let val (evs,bod) = strip_exists tm0 val (avs,ibod) = strip_forall bod val th1 = Drule.arg_cong_rule \<^cterm>\Trueprop\ (fold mk_forall avs (absremover ibod)) val (th2, certs) = overall [] [] [specl avs (Thm.assume (Thm.rhs_of th1))] val th3 = fold simple_choose evs (prove_hyp (Thm.equal_elim th1 (Thm.assume (Thm.apply \<^cterm>\Trueprop\ bod))) th2) in (Drule.implies_intr_hyps (prove_hyp (Thm.equal_elim th0 (Thm.assume nct)) th3), certs) end in (Thm.implies_elim (Thm.instantiate' [] [SOME ct] pth_final) th, certificates) end in f end; (* A linear arithmetic prover *) local val linear_add = FuncUtil.Ctermfunc.combine (curry op +) (fn z => z = @0) fun linear_cmul c = FuncUtil.Ctermfunc.map (fn _ => fn x => c * x) val one_tm = \<^cterm>\1::real\ fun contradictory p (e,_) = ((FuncUtil.Ctermfunc.is_empty e) andalso not(p @0)) orelse ((eq_set (op aconvc) (FuncUtil.Ctermfunc.dom e, [one_tm])) andalso not(p(FuncUtil.Ctermfunc.apply e one_tm))) fun linear_ineqs vars (les,lts) = case find_first (contradictory (fn x => x > @0)) lts of SOME r => r | NONE => (case find_first (contradictory (fn x => x > @0)) les of SOME r => r | NONE => if null vars then error "linear_ineqs: no contradiction" else let val ineqs = les @ lts fun blowup v = length(filter (fn (e,_) => FuncUtil.Ctermfunc.tryapplyd e v @0 = @0) ineqs) + length(filter (fn (e,_) => FuncUtil.Ctermfunc.tryapplyd e v @0 > @0) ineqs) * length(filter (fn (e,_) => FuncUtil.Ctermfunc.tryapplyd e v @0 < @0) ineqs) val v = fst(hd(sort (fn ((_,i),(_,j)) => int_ord (i,j)) (map (fn v => (v,blowup v)) vars))) fun addup (e1,p1) (e2,p2) acc = let val c1 = FuncUtil.Ctermfunc.tryapplyd e1 v @0 val c2 = FuncUtil.Ctermfunc.tryapplyd e2 v @0 in if c1 * c2 >= @0 then acc else let val e1' = linear_cmul (abs c2) e1 val e2' = linear_cmul (abs c1) e2 val p1' = Product(Rational_lt (abs c2), p1) val p2' = Product(Rational_lt (abs c1), p2) in (linear_add e1' e2',Sum(p1',p2'))::acc end end val (les0,les1) = List.partition (fn (e,_) => FuncUtil.Ctermfunc.tryapplyd e v @0 = @0) les val (lts0,lts1) = List.partition (fn (e,_) => FuncUtil.Ctermfunc.tryapplyd e v @0 = @0) lts val (lesp,lesn) = List.partition (fn (e,_) => FuncUtil.Ctermfunc.tryapplyd e v @0 > @0) les1 val (ltsp,ltsn) = List.partition (fn (e,_) => FuncUtil.Ctermfunc.tryapplyd e v @0 > @0) lts1 val les' = fold_rev (fn ep1 => fold_rev (addup ep1) lesp) lesn les0 val lts' = fold_rev (fn ep1 => fold_rev (addup ep1) (lesp@ltsp)) ltsn (fold_rev (fn ep1 => fold_rev (addup ep1) (lesn@ltsn)) ltsp lts0) in linear_ineqs (remove (op aconvc) v vars) (les',lts') end) fun linear_eqs(eqs,les,lts) = case find_first (contradictory (fn x => x = @0)) eqs of SOME r => r | NONE => (case eqs of [] => let val vars = remove (op aconvc) one_tm (fold_rev (union (op aconvc) o FuncUtil.Ctermfunc.dom o fst) (les@lts) []) in linear_ineqs vars (les,lts) end | (e,p)::es => if FuncUtil.Ctermfunc.is_empty e then linear_eqs (es,les,lts) else let val (x,c) = FuncUtil.Ctermfunc.choose (FuncUtil.Ctermfunc.delete_safe one_tm e) fun xform (inp as (t,q)) = let val d = FuncUtil.Ctermfunc.tryapplyd t x @0 in if d = @0 then inp else let val k = ~ d * abs c / c val e' = linear_cmul k e val t' = linear_cmul (abs c) t val p' = Eqmul(FuncUtil.Monomialfunc.onefunc (FuncUtil.Ctermfunc.empty, k),p) val q' = Product(Rational_lt (abs c), q) in (linear_add e' t',Sum(p',q')) end end in linear_eqs(map xform es,map xform les,map xform lts) end) fun linear_prover (eq,le,lt) = let val eqs = map_index (fn (n, p) => (p,Axiom_eq n)) eq val les = map_index (fn (n, p) => (p,Axiom_le n)) le val lts = map_index (fn (n, p) => (p,Axiom_lt n)) lt in linear_eqs(eqs,les,lts) end fun lin_of_hol ct = if ct aconvc \<^cterm>\0::real\ then FuncUtil.Ctermfunc.empty else if not (is_comb ct) then FuncUtil.Ctermfunc.onefunc (ct, @1) else if is_ratconst ct then FuncUtil.Ctermfunc.onefunc (one_tm, dest_ratconst ct) else let val (lop,r) = Thm.dest_comb ct in if not (is_comb lop) then FuncUtil.Ctermfunc.onefunc (ct, @1) else let val (opr,l) = Thm.dest_comb lop in if opr aconvc \<^cterm>\(+) :: real \ _\ then linear_add (lin_of_hol l) (lin_of_hol r) else if opr aconvc \<^cterm>\(*) :: real \ _\ andalso is_ratconst l then FuncUtil.Ctermfunc.onefunc (r, dest_ratconst l) else FuncUtil.Ctermfunc.onefunc (ct, @1) end end fun is_alien ct = case Thm.term_of ct of - Const(\<^const_name>\of_nat\, _)$ n => not (can HOLogic.dest_number n) - | Const(\<^const_name>\of_int\, _)$ n => not (can HOLogic.dest_number n) + \<^Const_>\of_nat _ for n\ => not (can HOLogic.dest_number n) + | \<^Const_>\of_int _ for n\ => not (can HOLogic.dest_number n) | _ => false in fun real_linear_prover translator (eq,le,lt) = let val lhs = lin_of_hol o Thm.dest_arg1 o Thm.dest_arg o Thm.cprop_of val rhs = lin_of_hol o Thm.dest_arg o Thm.dest_arg o Thm.cprop_of val eq_pols = map lhs eq val le_pols = map rhs le val lt_pols = map rhs lt val aliens = filter is_alien (fold_rev (union (op aconvc) o FuncUtil.Ctermfunc.dom) (eq_pols @ le_pols @ lt_pols) []) val le_pols' = le_pols @ map (fn v => FuncUtil.Ctermfunc.onefunc (v,@1)) aliens val (_,proof) = linear_prover (eq_pols,le_pols',lt_pols) val le' = le @ map (fn a => Thm.instantiate' [] [SOME (Thm.dest_arg a)] @{thm of_nat_0_le_iff}) aliens in ((translator (eq,le',lt) proof), Trivial) end end; (* A less general generic arithmetic prover dealing with abs,max and min*) local val absmaxmin_elim_ss1 = simpset_of (put_simpset HOL_basic_ss \<^context> addsimps real_abs_thms1) fun absmaxmin_elim_conv1 ctxt = Simplifier.rewrite (put_simpset absmaxmin_elim_ss1 ctxt) val absmaxmin_elim_conv2 = let val pth_abs = Thm.instantiate' [SOME \<^ctyp>\real\] [] abs_split' val pth_max = Thm.instantiate' [SOME \<^ctyp>\real\] [] max_split val pth_min = Thm.instantiate' [SOME \<^ctyp>\real\] [] min_split val abs_tm = \<^cterm>\abs :: real \ _\ val p_v = (("P", 0), \<^typ>\real \ bool\) val x_v = (("x", 0), \<^typ>\real\) val y_v = (("y", 0), \<^typ>\real\) val is_max = is_binop \<^cterm>\max :: real \ _\ val is_min = is_binop \<^cterm>\min :: real \ _\ fun is_abs t = is_comb t andalso Thm.dest_fun t aconvc abs_tm fun eliminate_construct p c tm = let val t = find_cterm p tm val th0 = (Thm.symmetric o Thm.beta_conversion false) (Thm.apply (Thm.lambda t tm) t) val (p,ax) = (Thm.dest_comb o Thm.rhs_of) th0 in fconv_rule(arg_conv(binop_conv (arg_conv (Thm.beta_conversion false)))) (Thm.transitive th0 (c p ax)) end val elim_abs = eliminate_construct is_abs (fn p => fn ax => Thm.instantiate (TVars.empty, Vars.make [(p_v,p), (x_v, Thm.dest_arg ax)]) pth_abs) val elim_max = eliminate_construct is_max (fn p => fn ax => let val (ax,y) = Thm.dest_comb ax in Thm.instantiate (TVars.empty, Vars.make [(p_v,p), (x_v, Thm.dest_arg ax), (y_v,y)]) pth_max end) val elim_min = eliminate_construct is_min (fn p => fn ax => let val (ax,y) = Thm.dest_comb ax in Thm.instantiate (TVars.empty, Vars.make [(p_v,p), (x_v, Thm.dest_arg ax), (y_v,y)]) pth_min end) in first_conv [elim_abs, elim_max, elim_min, all_conv] end; in fun gen_real_arith ctxt (mkconst,eq,ge,gt,norm,neg,add,mul,prover) = gen_gen_real_arith ctxt (mkconst,eq,ge,gt,norm,neg,add,mul, absmaxmin_elim_conv1 ctxt,absmaxmin_elim_conv2,prover) end; (* An instance for reals*) fun gen_prover_real_arith ctxt prover = let val {add, mul, neg, pow = _, sub = _, main} = Semiring_Normalizer.semiring_normalizers_ord_wrapper ctxt (the (Semiring_Normalizer.match ctxt \<^cterm>\(0::real) + 1\)) Thm.term_ord in gen_real_arith ctxt (cterm_of_rat, Numeral_Simprocs.field_comp_conv ctxt, Numeral_Simprocs.field_comp_conv ctxt, Numeral_Simprocs.field_comp_conv ctxt, main ctxt, neg ctxt, add ctxt, mul ctxt, prover) end; end