src/HOL/Real/Real.ML
changeset 5588 a3ab526bb891
parent 5535 678999604ee9
child 6162 484adda70b65
equal deleted inserted replaced
5587:7fceb6eea475 5588:a3ab526bb891
     1 (*  Title       : Real.ML
     1 (*  Title:      HOL/Real/Real.ML
     2     Author      : Jacques D. Fleuriot
     2     ID:         $Id$
     3     Copyright   : 1998  University of Cambridge
     3     Author:     Lawrence C Paulson, Cambridge University Computer Laboratory
     4     Description : The reals
     4     Copyright   1998  University of Cambridge
       
     5 
       
     6 Type "real" is a linear order
     5 *)
     7 *)
     6 
     8 
     7 (*** Proving that realrel is an equivalence relation ***)
     9 
     8 
       
     9 Goal "[| (x1::preal) + y2 = x2 + y1; x2 + y3 = x3 + y2 |] \
       
    10 \            ==> x1 + y3 = x3 + y1";        
       
    11 by (res_inst_tac [("C","y2")] preal_add_right_cancel 1);
       
    12 by (rotate_tac 1 1 THEN dtac sym 1);
       
    13 by (asm_full_simp_tac (simpset() addsimps preal_add_ac) 1);
       
    14 by (rtac (preal_add_left_commute RS subst) 1);
       
    15 by (res_inst_tac [("x1","x1")] (preal_add_assoc RS subst) 1);
       
    16 by (asm_full_simp_tac (simpset() addsimps preal_add_ac) 1);
       
    17 qed "preal_trans_lemma";
       
    18 
       
    19 (** Natural deduction for realrel **)
       
    20 
       
    21 Goalw [realrel_def]
       
    22     "(((x1,y1),(x2,y2)): realrel) = (x1 + y2 = x2 + y1)";
       
    23 by (Blast_tac 1);
       
    24 qed "realrel_iff";
       
    25 
       
    26 Goalw [realrel_def]
       
    27     "[| x1 + y2 = x2 + y1 |] ==> ((x1,y1),(x2,y2)): realrel";
       
    28 by (Blast_tac  1);
       
    29 qed "realrelI";
       
    30 
       
    31 Goalw [realrel_def]
       
    32   "p: realrel --> (EX x1 y1 x2 y2. \
       
    33 \                  p = ((x1,y1),(x2,y2)) & x1 + y2 = x2 + y1)";
       
    34 by (Blast_tac 1);
       
    35 qed "realrelE_lemma";
       
    36 
       
    37 val [major,minor] = goal thy
       
    38   "[| p: realrel;  \
       
    39 \     !!x1 y1 x2 y2. [| p = ((x1,y1),(x2,y2));  x1+y2 = x2+y1 \
       
    40 \                    |] ==> Q |] ==> Q";
       
    41 by (cut_facts_tac [major RS (realrelE_lemma RS mp)] 1);
       
    42 by (REPEAT (eresolve_tac [asm_rl,exE,conjE,minor] 1));
       
    43 qed "realrelE";
       
    44 
       
    45 AddSIs [realrelI];
       
    46 AddSEs [realrelE];
       
    47 
       
    48 Goal "(x,x): realrel";
       
    49 by (stac surjective_pairing 1 THEN rtac (refl RS realrelI) 1);
       
    50 qed "realrel_refl";
       
    51 
       
    52 Goalw [equiv_def, refl_def, sym_def, trans_def]
       
    53     "equiv {x::(preal*preal).True} realrel";
       
    54 by (fast_tac (claset() addSIs [realrel_refl] 
       
    55                       addSEs [sym,preal_trans_lemma]) 1);
       
    56 qed "equiv_realrel";
       
    57 
       
    58 val equiv_realrel_iff =
       
    59     [TrueI, TrueI] MRS 
       
    60     ([CollectI, CollectI] MRS 
       
    61     (equiv_realrel RS eq_equiv_class_iff));
       
    62 
       
    63 Goalw  [real_def,realrel_def,quotient_def] "realrel^^{(x,y)}:real";
       
    64 by (Blast_tac 1);
       
    65 qed "realrel_in_real";
       
    66 
       
    67 Goal "inj_on Abs_real real";
       
    68 by (rtac inj_on_inverseI 1);
       
    69 by (etac Abs_real_inverse 1);
       
    70 qed "inj_on_Abs_real";
       
    71 
       
    72 Addsimps [equiv_realrel_iff,inj_on_Abs_real RS inj_on_iff,
       
    73           realrel_iff, realrel_in_real, Abs_real_inverse];
       
    74 
       
    75 Addsimps [equiv_realrel RS eq_equiv_class_iff];
       
    76 val eq_realrelD = equiv_realrel RSN (2,eq_equiv_class);
       
    77 
       
    78 Goal "inj(Rep_real)";
       
    79 by (rtac inj_inverseI 1);
       
    80 by (rtac Rep_real_inverse 1);
       
    81 qed "inj_Rep_real";
       
    82 
       
    83 (** real_preal: the injection from preal to real **)
       
    84 Goal "inj(real_preal)";
       
    85 by (rtac injI 1);
       
    86 by (rewtac real_preal_def);
       
    87 by (dtac (inj_on_Abs_real RS inj_onD) 1);
       
    88 by (REPEAT (rtac realrel_in_real 1));
       
    89 by (dtac eq_equiv_class 1);
       
    90 by (rtac equiv_realrel 1);
       
    91 by (Blast_tac 1);
       
    92 by Safe_tac;
       
    93 by (Asm_full_simp_tac 1);
       
    94 qed "inj_real_preal";
       
    95 
       
    96 val [prem] = goal thy
       
    97     "(!!x y. z = Abs_real(realrel^^{(x,y)}) ==> P) ==> P";
       
    98 by (res_inst_tac [("x1","z")] 
       
    99     (rewrite_rule [real_def] Rep_real RS quotientE) 1);
       
   100 by (dres_inst_tac [("f","Abs_real")] arg_cong 1);
       
   101 by (res_inst_tac [("p","x")] PairE 1);
       
   102 by (rtac prem 1);
       
   103 by (asm_full_simp_tac (simpset() addsimps [Rep_real_inverse]) 1);
       
   104 qed "eq_Abs_real";
       
   105 
       
   106 (**** real_minus: additive inverse on real ****)
       
   107 
       
   108 Goalw [congruent_def]
       
   109   "congruent realrel (%p. split (%x y. realrel^^{(y,x)}) p)";
       
   110 by Safe_tac;
       
   111 by (asm_full_simp_tac (simpset() addsimps [preal_add_commute]) 1);
       
   112 qed "real_minus_congruent";
       
   113 
       
   114 (*Resolve th against the corresponding facts for real_minus*)
       
   115 val real_minus_ize = RSLIST [equiv_realrel, real_minus_congruent];
       
   116 
       
   117 Goalw [real_minus_def]
       
   118       "%~ (Abs_real(realrel^^{(x,y)})) = Abs_real(realrel ^^ {(y,x)})";
       
   119 by (res_inst_tac [("f","Abs_real")] arg_cong 1);
       
   120 by (simp_tac (simpset() addsimps 
       
   121    [realrel_in_real RS Abs_real_inverse,real_minus_ize UN_equiv_class]) 1);
       
   122 qed "real_minus";
       
   123 
       
   124 Goal "%~ (%~ z) = z";
       
   125 by (res_inst_tac [("z","z")] eq_Abs_real 1);
       
   126 by (asm_simp_tac (simpset() addsimps [real_minus]) 1);
       
   127 qed "real_minus_minus";
       
   128 
       
   129 Addsimps [real_minus_minus];
       
   130 
       
   131 Goal "inj(real_minus)";
       
   132 by (rtac injI 1);
       
   133 by (dres_inst_tac [("f","real_minus")] arg_cong 1);
       
   134 by (asm_full_simp_tac (simpset() addsimps [real_minus_minus]) 1);
       
   135 qed "inj_real_minus";
       
   136 
       
   137 Goalw [real_zero_def] "%~0r = 0r";
       
   138 by (simp_tac (simpset() addsimps [real_minus]) 1);
       
   139 qed "real_minus_zero";
       
   140 
       
   141 Addsimps [real_minus_zero];
       
   142 
       
   143 Goal "(%~x = 0r) = (x = 0r)"; 
       
   144 by (res_inst_tac [("z","x")] eq_Abs_real 1);
       
   145 by (auto_tac (claset(),simpset() addsimps [real_zero_def,
       
   146     real_minus] @ preal_add_ac));
       
   147 qed "real_minus_zero_iff";
       
   148 
       
   149 Addsimps [real_minus_zero_iff];
       
   150 
       
   151 Goal "(%~x ~= 0r) = (x ~= 0r)"; 
       
   152 by Auto_tac;
       
   153 qed "real_minus_not_zero_iff";
       
   154 
       
   155 (*** Congruence property for addition ***)
       
   156 Goalw [congruent2_def]
       
   157     "congruent2 realrel (%p1 p2.                  \
       
   158 \         split (%x1 y1. split (%x2 y2. realrel^^{(x1+x2, y1+y2)}) p2) p1)";
       
   159 by Safe_tac;
       
   160 by (asm_simp_tac (simpset() addsimps [preal_add_assoc]) 1);
       
   161 by (res_inst_tac [("z1.1","x1a")] (preal_add_left_commute RS ssubst) 1);
       
   162 by (asm_simp_tac (simpset() addsimps [preal_add_assoc RS sym]) 1);
       
   163 by (asm_simp_tac (simpset() addsimps preal_add_ac) 1);
       
   164 qed "real_add_congruent2";
       
   165 
       
   166 (*Resolve th against the corresponding facts for real_add*)
       
   167 val real_add_ize = RSLIST [equiv_realrel, real_add_congruent2];
       
   168 
       
   169 Goalw [real_add_def]
       
   170   "Abs_real(realrel^^{(x1,y1)}) + Abs_real(realrel^^{(x2,y2)}) = \
       
   171 \  Abs_real(realrel^^{(x1+x2, y1+y2)})";
       
   172 by (asm_simp_tac
       
   173     (simpset() addsimps [real_add_ize UN_equiv_class2]) 1);
       
   174 qed "real_add";
       
   175 
       
   176 Goal "(z::real) + w = w + z";
       
   177 by (res_inst_tac [("z","z")] eq_Abs_real 1);
       
   178 by (res_inst_tac [("z","w")] eq_Abs_real 1);
       
   179 by (asm_simp_tac (simpset() addsimps preal_add_ac @ [real_add]) 1);
       
   180 qed "real_add_commute";
       
   181 
       
   182 Goal "((z1::real) + z2) + z3 = z1 + (z2 + z3)";
       
   183 by (res_inst_tac [("z","z1")] eq_Abs_real 1);
       
   184 by (res_inst_tac [("z","z2")] eq_Abs_real 1);
       
   185 by (res_inst_tac [("z","z3")] eq_Abs_real 1);
       
   186 by (asm_simp_tac (simpset() addsimps [real_add, preal_add_assoc]) 1);
       
   187 qed "real_add_assoc";
       
   188 
       
   189 (*For AC rewriting*)
       
   190 Goal "(x::real)+(y+z)=y+(x+z)";
       
   191 by (rtac (real_add_commute RS trans) 1);
       
   192 by (rtac (real_add_assoc RS trans) 1);
       
   193 by (rtac (real_add_commute RS arg_cong) 1);
       
   194 qed "real_add_left_commute";
       
   195 
       
   196 (* real addition is an AC operator *)
       
   197 val real_add_ac = [real_add_assoc,real_add_commute,real_add_left_commute];
       
   198 
       
   199 Goalw [real_preal_def,real_zero_def] "0r + z = z";
       
   200 by (res_inst_tac [("z","z")] eq_Abs_real 1);
       
   201 by (asm_full_simp_tac (simpset() addsimps [real_add] @ preal_add_ac) 1);
       
   202 qed "real_add_zero_left";
       
   203 
       
   204 Goal "z + 0r = z";
       
   205 by (simp_tac (simpset() addsimps [real_add_zero_left,real_add_commute]) 1);
       
   206 qed "real_add_zero_right";
       
   207 
       
   208 Goalw [real_zero_def] "z + %~z = 0r";
       
   209 by (res_inst_tac [("z","z")] eq_Abs_real 1);
       
   210 by (asm_full_simp_tac (simpset() addsimps [real_minus,
       
   211         real_add, preal_add_commute]) 1);
       
   212 qed "real_add_minus";
       
   213 
       
   214 Goal "%~z + z = 0r";
       
   215 by (simp_tac (simpset() addsimps 
       
   216     [real_add_commute,real_add_minus]) 1);
       
   217 qed "real_add_minus_left";
       
   218 
       
   219 Goal "? y. (x::real) + y = 0r";
       
   220 by (blast_tac (claset() addIs [real_add_minus]) 1);
       
   221 qed "real_minus_ex";
       
   222 
       
   223 Goal "?! y. (x::real) + y = 0r";
       
   224 by (auto_tac (claset() addIs [real_add_minus],simpset()));
       
   225 by (dres_inst_tac [("f","%x. ya+x")] arg_cong 1);
       
   226 by (asm_full_simp_tac (simpset() addsimps [real_add_assoc RS sym]) 1);
       
   227 by (asm_full_simp_tac (simpset() addsimps [real_add_commute,
       
   228     real_add_zero_right,real_add_zero_left]) 1);
       
   229 qed "real_minus_ex1";
       
   230 
       
   231 Goal "?! y. y + (x::real) = 0r";
       
   232 by (auto_tac (claset() addIs [real_add_minus_left],simpset()));
       
   233 by (dres_inst_tac [("f","%x. x+ya")] arg_cong 1);
       
   234 by (asm_full_simp_tac (simpset() addsimps [real_add_assoc]) 1);
       
   235 by (asm_full_simp_tac (simpset() addsimps [real_add_commute,
       
   236     real_add_zero_right,real_add_zero_left]) 1);
       
   237 qed "real_minus_left_ex1";
       
   238 
       
   239 Goal "x + y = 0r ==> x = %~y";
       
   240 by (cut_inst_tac [("z","y")] real_add_minus_left 1);
       
   241 by (res_inst_tac [("x1","y")] (real_minus_left_ex1 RS ex1E) 1);
       
   242 by (Blast_tac 1);
       
   243 qed "real_add_minus_eq_minus";
       
   244 
       
   245 Goal "? y. x = %~y";
       
   246 by (cut_inst_tac [("x","x")] real_minus_ex 1);
       
   247 by (etac exE 1 THEN dtac real_add_minus_eq_minus 1);
       
   248 by (Blast_tac 1);
       
   249 qed "real_as_add_inverse_ex";
       
   250 
       
   251 (* real_minus_add_distrib *)
       
   252 Goal "%~(x + y) = %~x + %~y";
       
   253 by (res_inst_tac [("z","x")] eq_Abs_real 1);
       
   254 by (res_inst_tac [("z","y")] eq_Abs_real 1);
       
   255 by (auto_tac (claset(),simpset() addsimps [real_minus,real_add]));
       
   256 qed "real_minus_add_eq";
       
   257 
       
   258 val real_minus_add_distrib = real_minus_add_eq;
       
   259 
       
   260 Goal "((x::real) + y = x + z) = (y = z)";
       
   261 by (Step_tac 1);
       
   262 by (dres_inst_tac [("f","%t.%~x + t")] arg_cong 1);
       
   263 by (asm_full_simp_tac (simpset() addsimps [real_add_minus_left,
       
   264                  real_add_assoc RS sym,real_add_zero_left]) 1);
       
   265 qed "real_add_left_cancel";
       
   266 
       
   267 Goal "(y + (x::real)= z + x) = (y = z)";
       
   268 by (simp_tac (simpset() addsimps [real_add_commute,real_add_left_cancel]) 1);
       
   269 qed "real_add_right_cancel";
       
   270 
       
   271 (*** Congruence property for multiplication ***)
       
   272 Goal "!!(x1::preal). [| x1 + y2 = x2 + y1 |] ==> \
       
   273 \         x * x1 + y * y1 + (x * y2 + x2 * y) = \
       
   274 \         x * x2 + y * y2 + (x * y1 + x1 * y)";
       
   275 by (asm_full_simp_tac (simpset() addsimps [preal_add_left_commute,
       
   276     preal_add_assoc RS sym,preal_add_mult_distrib2 RS sym]) 1);
       
   277 by (rtac (preal_mult_commute RS subst) 1);
       
   278 by (res_inst_tac [("y1","x2")] (preal_mult_commute RS subst) 1);
       
   279 by (asm_full_simp_tac (simpset() addsimps [preal_add_assoc,
       
   280     preal_add_mult_distrib2 RS sym]) 1);
       
   281 by (asm_full_simp_tac (simpset() addsimps [preal_add_commute]) 1);
       
   282 qed "real_mult_congruent2_lemma";
       
   283 
       
   284 Goal 
       
   285     "congruent2 realrel (%p1 p2.                  \
       
   286 \         split (%x1 y1. split (%x2 y2. realrel^^{(x1*x2 + y1*y2, x1*y2+x2*y1)}) p2) p1)";
       
   287 by (rtac (equiv_realrel RS congruent2_commuteI) 1);
       
   288 by Safe_tac;
       
   289 by (rewtac split_def);
       
   290 by (asm_simp_tac (simpset() addsimps [preal_mult_commute,preal_add_commute]) 1);
       
   291 by (auto_tac (claset(),simpset() addsimps [real_mult_congruent2_lemma]));
       
   292 qed "real_mult_congruent2";
       
   293 
       
   294 (*Resolve th against the corresponding facts for real_mult*)
       
   295 val real_mult_ize = RSLIST [equiv_realrel, real_mult_congruent2];
       
   296 
       
   297 Goalw [real_mult_def]
       
   298    "Abs_real((realrel^^{(x1,y1)})) * Abs_real((realrel^^{(x2,y2)})) =   \
       
   299 \   Abs_real(realrel ^^ {(x1*x2+y1*y2,x1*y2+x2*y1)})";
       
   300 by (simp_tac (simpset() addsimps [real_mult_ize UN_equiv_class2]) 1);
       
   301 qed "real_mult";
       
   302 
       
   303 Goal "(z::real) * w = w * z";
       
   304 by (res_inst_tac [("z","z")] eq_Abs_real 1);
       
   305 by (res_inst_tac [("z","w")] eq_Abs_real 1);
       
   306 by (asm_simp_tac
       
   307     (simpset() addsimps [real_mult] @ preal_add_ac @ preal_mult_ac) 1);
       
   308 qed "real_mult_commute";
       
   309 
       
   310 Goal "((z1::real) * z2) * z3 = z1 * (z2 * z3)";
       
   311 by (res_inst_tac [("z","z1")] eq_Abs_real 1);
       
   312 by (res_inst_tac [("z","z2")] eq_Abs_real 1);
       
   313 by (res_inst_tac [("z","z3")] eq_Abs_real 1);
       
   314 by (asm_simp_tac (simpset() addsimps [preal_add_mult_distrib2,real_mult] @ 
       
   315                                      preal_add_ac @ preal_mult_ac) 1);
       
   316 qed "real_mult_assoc";
       
   317 
       
   318 qed_goal "real_mult_left_commute" thy
       
   319     "(z1::real) * (z2 * z3) = z2 * (z1 * z3)"
       
   320  (fn _ => [rtac (real_mult_commute RS trans) 1, rtac (real_mult_assoc RS trans) 1,
       
   321            rtac (real_mult_commute RS arg_cong) 1]);
       
   322 
       
   323 (* real multiplication is an AC operator *)
       
   324 val real_mult_ac = [real_mult_assoc, real_mult_commute, real_mult_left_commute];
       
   325 
       
   326 Goalw [real_one_def,pnat_one_def] "1r * z = z";
       
   327 by (res_inst_tac [("z","z")] eq_Abs_real 1);
       
   328 by (asm_full_simp_tac (simpset() addsimps [real_mult,
       
   329     preal_add_mult_distrib2,preal_mult_1_right] 
       
   330     @ preal_mult_ac @ preal_add_ac) 1);
       
   331 qed "real_mult_1";
       
   332 
       
   333 Goal "z * 1r = z";
       
   334 by (simp_tac (simpset() addsimps [real_mult_commute,
       
   335     real_mult_1]) 1);
       
   336 qed "real_mult_1_right";
       
   337 
       
   338 Goalw [real_zero_def,pnat_one_def] "0r * z = 0r";
       
   339 by (res_inst_tac [("z","z")] eq_Abs_real 1);
       
   340 by (asm_full_simp_tac (simpset() addsimps [real_mult,
       
   341     preal_add_mult_distrib2,preal_mult_1_right] 
       
   342     @ preal_mult_ac @ preal_add_ac) 1);
       
   343 qed "real_mult_0";
       
   344 
       
   345 Goal "z * 0r = 0r";
       
   346 by (simp_tac (simpset() addsimps [real_mult_commute,
       
   347     real_mult_0]) 1);
       
   348 qed "real_mult_0_right";
       
   349 
       
   350 Addsimps [real_mult_0_right,real_mult_0];
       
   351 
       
   352 Goal "%~(x * y) = %~x * y";
       
   353 by (res_inst_tac [("z","x")] eq_Abs_real 1);
       
   354 by (res_inst_tac [("z","y")] eq_Abs_real 1);
       
   355 by (auto_tac (claset(),simpset() addsimps [real_minus,real_mult] 
       
   356     @ preal_mult_ac @ preal_add_ac));
       
   357 qed "real_minus_mult_eq1";
       
   358 
       
   359 Goal "%~(x * y) = x * %~y";
       
   360 by (res_inst_tac [("z","x")] eq_Abs_real 1);
       
   361 by (res_inst_tac [("z","y")] eq_Abs_real 1);
       
   362 by (auto_tac (claset(),simpset() addsimps [real_minus,real_mult] 
       
   363     @ preal_mult_ac @ preal_add_ac));
       
   364 qed "real_minus_mult_eq2";
       
   365 
       
   366 Goal "%~x*%~y = x*y";
       
   367 by (full_simp_tac (simpset() addsimps [real_minus_mult_eq2 RS sym,
       
   368     real_minus_mult_eq1 RS sym]) 1);
       
   369 qed "real_minus_mult_cancel";
       
   370 
       
   371 Addsimps [real_minus_mult_cancel];
       
   372 
       
   373 Goal "%~x*y = x*%~y";
       
   374 by (full_simp_tac (simpset() addsimps [real_minus_mult_eq2 RS sym,
       
   375     real_minus_mult_eq1 RS sym]) 1);
       
   376 qed "real_minus_mult_commute";
       
   377 
       
   378 (*-----------------------------------------------------------------------------
       
   379 
       
   380  -----------------------------------------------------------------------------*)
       
   381 
       
   382 (** Lemmas **)
       
   383 
       
   384 qed_goal "real_add_assoc_cong" thy
       
   385     "!!z. (z::real) + v = z' + v' ==> z + (v + w) = z' + (v' + w)"
       
   386  (fn _ => [(asm_simp_tac (simpset() addsimps [real_add_assoc RS sym]) 1)]);
       
   387 
       
   388 qed_goal "real_add_assoc_swap" thy "(z::real) + (v + w) = v + (z + w)"
       
   389  (fn _ => [(REPEAT (ares_tac [real_add_commute RS real_add_assoc_cong] 1))]);
       
   390 
       
   391 Goal "((z1::real) + z2) * w = (z1 * w) + (z2 * w)";
       
   392 by (res_inst_tac [("z","z1")] eq_Abs_real 1);
       
   393 by (res_inst_tac [("z","z2")] eq_Abs_real 1);
       
   394 by (res_inst_tac [("z","w")] eq_Abs_real 1);
       
   395 by (asm_simp_tac 
       
   396     (simpset() addsimps [preal_add_mult_distrib2, real_add, real_mult] @ 
       
   397                         preal_add_ac @ preal_mult_ac) 1);
       
   398 qed "real_add_mult_distrib";
       
   399 
       
   400 val real_mult_commute'= read_instantiate [("z","w")] real_mult_commute;
       
   401 
       
   402 Goal "(w::real) * (z1 + z2) = (w * z1) + (w * z2)";
       
   403 by (simp_tac (simpset() addsimps [real_mult_commute',real_add_mult_distrib]) 1);
       
   404 qed "real_add_mult_distrib2";
       
   405 
       
   406 val real_mult_simps = [real_mult_1, real_mult_1_right];
       
   407 Addsimps real_mult_simps;
       
   408 
       
   409 (*** one and zero are distinct ***)
       
   410 Goalw [real_zero_def,real_one_def] "0r ~= 1r";
       
   411 by (auto_tac (claset(),simpset() addsimps 
       
   412    [preal_self_less_add_left RS preal_not_refl2]));
       
   413 qed "real_zero_not_eq_one";
       
   414 
       
   415 (*** existence of inverse ***)
       
   416 (** lemma -- alternative definition for 0r **)
       
   417 Goalw [real_zero_def] "0r = Abs_real (realrel ^^ {(x, x)})";
       
   418 by (auto_tac (claset(),simpset() addsimps [preal_add_commute]));
       
   419 qed "real_zero_iff";
       
   420 
       
   421 Goalw [real_zero_def,real_one_def] 
       
   422           "!!(x::real). x ~= 0r ==> ? y. x*y = 1r";
       
   423 by (res_inst_tac [("z","x")] eq_Abs_real 1);
       
   424 by (cut_inst_tac [("r1.0","xa"),("r2.0","y")] preal_linear 1);
       
   425 by (auto_tac (claset() addSDs [preal_less_add_left_Ex],
       
   426            simpset() addsimps [real_zero_iff RS sym]));
       
   427 by (res_inst_tac [("x","Abs_real (realrel ^^ {(@#$#1p,pinv(D)+@#$#1p)})")] exI 1);
       
   428 by (res_inst_tac [("x","Abs_real (realrel ^^ {(pinv(D)+@#$#1p,@#$#1p)})")] exI 2);
       
   429 by (auto_tac (claset(),simpset() addsimps [real_mult,
       
   430     pnat_one_def,preal_mult_1_right,preal_add_mult_distrib2,
       
   431     preal_add_mult_distrib,preal_mult_1,preal_mult_inv_right] 
       
   432     @ preal_add_ac @ preal_mult_ac));
       
   433 qed "real_mult_inv_right_ex";
       
   434 
       
   435 Goal "!!(x::real). x ~= 0r ==> ? y. y*x = 1r";
       
   436 by (asm_simp_tac (simpset() addsimps [real_mult_commute,
       
   437     real_mult_inv_right_ex]) 1);
       
   438 qed "real_mult_inv_left_ex";
       
   439 
       
   440 Goalw [rinv_def] "!!(x::real). x ~= 0r ==> rinv(x)*x = 1r";
       
   441 by (forward_tac [real_mult_inv_left_ex] 1);
       
   442 by (Step_tac 1);
       
   443 by (rtac selectI2 1);
       
   444 by Auto_tac;
       
   445 qed "real_mult_inv_left";
       
   446 
       
   447 Goal "!!(x::real). x ~= 0r ==> x*rinv(x) = 1r";
       
   448 by (auto_tac (claset() addIs [real_mult_commute RS subst],
       
   449               simpset() addsimps [real_mult_inv_left]));
       
   450 qed "real_mult_inv_right";
       
   451 
       
   452 Goal "(c::real) ~= 0r ==> (c*a=c*b) = (a=b)";
       
   453 by Auto_tac;
       
   454 by (dres_inst_tac [("f","%x. x*rinv c")] arg_cong 1);
       
   455 by (asm_full_simp_tac (simpset() addsimps [real_mult_inv_right] @ real_mult_ac)  1);
       
   456 qed "real_mult_left_cancel";
       
   457     
       
   458 Goal "(c::real) ~= 0r ==> (a*c=b*c) = (a=b)";
       
   459 by (Step_tac 1);
       
   460 by (dres_inst_tac [("f","%x. x*rinv c")] arg_cong 1);
       
   461 by (asm_full_simp_tac (simpset() addsimps [real_mult_inv_right] @ real_mult_ac)  1);
       
   462 qed "real_mult_right_cancel";
       
   463 
       
   464 Goalw [rinv_def] "x ~= 0r ==> rinv(x) ~= 0r";
       
   465 by (forward_tac [real_mult_inv_left_ex] 1);
       
   466 by (etac exE 1);
       
   467 by (rtac selectI2 1);
       
   468 by (auto_tac (claset(),simpset() addsimps [real_mult_0,
       
   469     real_zero_not_eq_one]));
       
   470 qed "rinv_not_zero";
       
   471 
       
   472 Addsimps [real_mult_inv_left,real_mult_inv_right];
       
   473 
       
   474 Goal "x ~= 0r ==> rinv(rinv x) = x";
       
   475 by (res_inst_tac [("c1","rinv x")] (real_mult_right_cancel RS iffD1) 1);
       
   476 by (etac rinv_not_zero 1);
       
   477 by (auto_tac (claset() addDs [rinv_not_zero],simpset()));
       
   478 qed "real_rinv_rinv";
       
   479 
       
   480 Goalw [rinv_def] "rinv(1r) = 1r";
       
   481 by (cut_facts_tac [real_zero_not_eq_one RS 
       
   482        not_sym RS real_mult_inv_left_ex] 1);
       
   483 by (etac exE 1);
       
   484 by (rtac selectI2 1);
       
   485 by (auto_tac (claset(),simpset() addsimps 
       
   486     [real_zero_not_eq_one RS not_sym]));
       
   487 qed "real_rinv_1";
       
   488 
       
   489 Goal "x ~= 0r ==> rinv(%~x) = %~rinv(x)";
       
   490 by (res_inst_tac [("c1","%~x")] (real_mult_right_cancel RS iffD1) 1);
       
   491 by Auto_tac;
       
   492 qed "real_minus_rinv";
       
   493 
       
   494       (*** theorems for ordering ***)
       
   495 (* prove introduction and elimination rules for real_less *)
       
   496 
       
   497 Goalw [real_less_def]
       
   498  "P < (Q::real) = (EX x1 y1 x2 y2. x1 + y2 < x2 + y1 & \
       
   499 \                                  (x1,y1::preal):Rep_real(P) & \
       
   500 \                                  (x2,y2):Rep_real(Q))";
       
   501 by (Blast_tac 1);
       
   502 qed "real_less_iff";
       
   503 
       
   504 Goalw [real_less_def]
       
   505  "[| x1 + y2 < x2 + y1; (x1,y1::preal):Rep_real(P); \
       
   506 \         (x2,y2):Rep_real(Q) |] ==> P < (Q::real)";
       
   507 by (Blast_tac 1);
       
   508 qed "real_lessI";
       
   509 
       
   510 Goalw [real_less_def]
       
   511  "!!P. [| R1 < (R2::real); \
       
   512 \         !!x1 x2 y1 y2. x1 + y2 < x2 + y1 ==> P; \
       
   513 \         !!x1 y1. (x1,y1::preal):Rep_real(R1) ==> P; \ 
       
   514 \         !!x2 y2. (x2,y2::preal):Rep_real(R2) ==> P |] \
       
   515 \     ==> P";
       
   516 by Auto_tac;
       
   517 qed "real_lessE";
       
   518 
       
   519 Goalw [real_less_def]
       
   520  "R1 < (R2::real) ==> (EX x1 y1 x2 y2. x1 + y2 < x2 + y1 & \
       
   521 \                                  (x1,y1::preal):Rep_real(R1) & \
       
   522 \                                  (x2,y2):Rep_real(R2))";
       
   523 by (Blast_tac 1);
       
   524 qed "real_lessD";
       
   525 
       
   526 (* real_less is a strong order i.e nonreflexive and transitive *)
       
   527 (*** lemmas ***)
       
   528 Goal "!!(x::preal). [| x = y; x1 = y1 |] ==> x + y1 = x1 + y";
       
   529 by (asm_simp_tac (simpset() addsimps [preal_add_commute]) 1);
       
   530 qed "preal_lemma_eq_rev_sum";
       
   531 
       
   532 Goal "!!(b::preal). x + (b + y) = x1 + (b + y1) ==> x + y = x1 + y1";
       
   533 by (asm_full_simp_tac (simpset() addsimps preal_add_ac) 1);
       
   534 qed "preal_add_left_commute_cancel";
       
   535 
       
   536 Goal 
       
   537      "!!(x::preal). [| x + y2a = x2a + y; \
       
   538 \                      x + y2b = x2b + y |] \
       
   539 \                   ==> x2a + y2b = x2b + y2a";
       
   540 by (dtac preal_lemma_eq_rev_sum 1);
       
   541 by (assume_tac 1);
       
   542 by (thin_tac "x + y2b = x2b + y" 1);
       
   543 by (asm_full_simp_tac (simpset() addsimps preal_add_ac) 1);
       
   544 by (dtac preal_add_left_commute_cancel 1);
       
   545 by (asm_full_simp_tac (simpset() addsimps preal_add_ac) 1);
       
   546 qed "preal_lemma_for_not_refl";
       
   547 
       
   548 Goal "~ (R::real) < R";
       
   549 by (res_inst_tac [("z","R")] eq_Abs_real 1);
       
   550 by (auto_tac (claset(),simpset() addsimps [real_less_def]));
       
   551 by (dtac preal_lemma_for_not_refl 1);
       
   552 by (assume_tac 1 THEN rotate_tac 2 1);
       
   553 by (auto_tac (claset(),simpset() addsimps [preal_less_not_refl]));
       
   554 qed "real_less_not_refl";
       
   555 
       
   556 (*** y < y ==> P ***)
       
   557 bind_thm("real_less_irrefl",real_less_not_refl RS notE);
       
   558 
       
   559 Goal "!!(x::real). x < y ==> x ~= y";
       
   560 by (auto_tac (claset(),simpset() addsimps [real_less_not_refl]));
       
   561 qed "real_not_refl2";
       
   562 
       
   563 (* lemma re-arranging and eliminating terms *)
       
   564 Goal "!! (a::preal). [| a + b = c + d; \
       
   565 \            x2b + d + (c + y2e) < a + y2b + (x2e + b) |] \
       
   566 \         ==> x2b + y2e < x2e + y2b";
       
   567 by (asm_full_simp_tac (simpset() addsimps preal_add_ac) 1);
       
   568 by (res_inst_tac [("C","c+d")] preal_add_left_less_cancel 1);
       
   569 by (asm_full_simp_tac (simpset() addsimps [preal_add_assoc RS sym]) 1);
       
   570 qed "preal_lemma_trans";
       
   571 
       
   572 (** heavy re-writing involved*)
       
   573 Goal "!!(R1::real). [| R1 < R2; R2 < R3 |] ==> R1 < R3";
       
   574 by (res_inst_tac [("z","R1")] eq_Abs_real 1);
       
   575 by (res_inst_tac [("z","R2")] eq_Abs_real 1);
       
   576 by (res_inst_tac [("z","R3")] eq_Abs_real 1);
       
   577 by (auto_tac (claset(),simpset() addsimps [real_less_def]));
       
   578 by (REPEAT(rtac exI 1));
       
   579 by (EVERY[rtac conjI 1, rtac conjI 2]);
       
   580 by (REPEAT(Blast_tac 2));
       
   581 by (dtac preal_lemma_for_not_refl 1 THEN assume_tac 1);
       
   582 by (blast_tac (claset() addDs [preal_add_less_mono] 
       
   583     addIs [preal_lemma_trans]) 1);
       
   584 qed "real_less_trans";
       
   585 
       
   586 Goal "!! (R1::real). [| R1 < R2; R2 < R1 |] ==> P";
       
   587 by (dtac real_less_trans 1 THEN assume_tac 1);
       
   588 by (asm_full_simp_tac (simpset() addsimps [real_less_not_refl]) 1);
       
   589 qed "real_less_asym";
       
   590 
       
   591 (****)(****)(****)(****)(****)(****)(****)(****)(****)(****)
       
   592     (****** Map and more real_less ******)
       
   593 (*** mapping from preal into real ***)
       
   594 Goalw [real_preal_def] 
       
   595             "%#((z1::preal) + z2) = %#z1 + %#z2";
       
   596 by (asm_simp_tac (simpset() addsimps [real_add,
       
   597        preal_add_mult_distrib,preal_mult_1] addsimps preal_add_ac) 1);
       
   598 qed "real_preal_add";
       
   599 
       
   600 Goalw [real_preal_def] 
       
   601             "%#((z1::preal) * z2) = %#z1* %#z2";
       
   602 by (full_simp_tac (simpset() addsimps [real_mult,
       
   603         preal_add_mult_distrib2,preal_mult_1,
       
   604         preal_mult_1_right,pnat_one_def] 
       
   605         @ preal_add_ac @ preal_mult_ac) 1);
       
   606 qed "real_preal_mult";
       
   607 
       
   608 Goalw [real_preal_def]
       
   609       "!!(x::preal). y < x ==> ? m. Abs_real (realrel ^^ {(x,y)}) = %#m";
       
   610 by (auto_tac (claset() addSDs [preal_less_add_left_Ex],
       
   611     simpset() addsimps preal_add_ac));
       
   612 qed "real_preal_ExI";
       
   613 
       
   614 Goalw [real_preal_def]
       
   615       "!!(x::preal). ? m. Abs_real (realrel ^^ {(x,y)}) = %#m ==> y < x";
       
   616 by (auto_tac (claset(),simpset() addsimps 
       
   617     [preal_add_commute,preal_add_assoc]));
       
   618 by (asm_full_simp_tac (simpset() addsimps 
       
   619     [preal_add_assoc RS sym,preal_self_less_add_left]) 1);
       
   620 qed "real_preal_ExD";
       
   621 
       
   622 Goal "(? m. Abs_real (realrel ^^ {(x,y)}) = %#m) = (y < x)";
       
   623 by (blast_tac (claset() addSIs [real_preal_ExI,real_preal_ExD]) 1);
       
   624 qed "real_preal_iff";
       
   625 
       
   626 (*** Gleason prop 9-4.4 p 127 ***)
       
   627 Goalw [real_preal_def,real_zero_def] 
       
   628       "? m. (x::real) = %#m | x = 0r | x = %~(%#m)";
       
   629 by (res_inst_tac [("z","x")] eq_Abs_real 1);
       
   630 by (auto_tac (claset(),simpset() addsimps [real_minus] @ preal_add_ac));
       
   631 by (cut_inst_tac [("r1.0","x"),("r2.0","y")] preal_linear 1);
       
   632 by (auto_tac (claset() addSDs [preal_less_add_left_Ex],
       
   633     simpset() addsimps [preal_add_assoc RS sym]));
       
   634 by (auto_tac (claset(),simpset() addsimps [preal_add_commute]));
       
   635 qed "real_preal_trichotomy";
       
   636 
       
   637 Goal "!!P. [| !!m. x = %#m ==> P; \
       
   638 \             x = 0r ==> P; \
       
   639 \             !!m. x = %~(%#m) ==> P |] ==> P";
       
   640 by (cut_inst_tac [("x","x")] real_preal_trichotomy 1);
       
   641 by Auto_tac;
       
   642 qed "real_preal_trichotomyE";
       
   643 
       
   644 Goalw [real_preal_def] "%#m1 < %#m2 ==> m1 < m2";
       
   645 by (auto_tac (claset(),simpset() addsimps [real_less_def] @ preal_add_ac));
       
   646 by (auto_tac (claset(),simpset() addsimps [preal_add_assoc RS sym]));
       
   647 by (auto_tac (claset(),simpset() addsimps preal_add_ac));
       
   648 qed "real_preal_lessD";
       
   649 
       
   650 Goal "m1 < m2 ==> %#m1 < %#m2";
       
   651 by (dtac preal_less_add_left_Ex 1);
       
   652 by (auto_tac (claset(),simpset() addsimps [real_preal_add,
       
   653     real_preal_def,real_less_def]));
       
   654 by (REPEAT(rtac exI 1));
       
   655 by (EVERY[rtac conjI 1, rtac conjI 2]);
       
   656 by (REPEAT(Blast_tac 2));
       
   657 by (simp_tac (simpset() addsimps [preal_self_less_add_left] 
       
   658     delsimps [preal_add_less_iff2]) 1);
       
   659 qed "real_preal_lessI";
       
   660 
       
   661 Goal "(%#m1 < %#m2) = (m1 < m2)";
       
   662 by (blast_tac (claset() addIs [real_preal_lessI,real_preal_lessD]) 1);
       
   663 qed "real_preal_less_iff1";
       
   664 
       
   665 Addsimps [real_preal_less_iff1];
       
   666 
       
   667 Goal "%~ %#m < %#m";
       
   668 by (auto_tac (claset(),simpset() addsimps 
       
   669     [real_preal_def,real_less_def,real_minus]));
       
   670 by (REPEAT(rtac exI 1));
       
   671 by (EVERY[rtac conjI 1, rtac conjI 2]);
       
   672 by (REPEAT(Blast_tac 2));
       
   673 by (full_simp_tac (simpset() addsimps preal_add_ac) 1);
       
   674 by (full_simp_tac (simpset() addsimps [preal_self_less_add_right,
       
   675     preal_add_assoc RS sym]) 1);
       
   676 qed "real_preal_minus_less_self";
       
   677 
       
   678 Goalw [real_zero_def] "%~ %#m < 0r";
       
   679 by (auto_tac (claset(),simpset() addsimps 
       
   680     [real_preal_def,real_less_def,real_minus]));
       
   681 by (REPEAT(rtac exI 1));
       
   682 by (EVERY[rtac conjI 1, rtac conjI 2]);
       
   683 by (REPEAT(Blast_tac 2));
       
   684 by (full_simp_tac (simpset() addsimps 
       
   685   [preal_self_less_add_right] @ preal_add_ac) 1);
       
   686 qed "real_preal_minus_less_zero";
       
   687 
       
   688 Goal "~ 0r < %~ %#m";
       
   689 by (cut_facts_tac [real_preal_minus_less_zero] 1);
       
   690 by (fast_tac (claset() addDs [real_less_trans] 
       
   691                         addEs [real_less_irrefl]) 1);
       
   692 qed "real_preal_not_minus_gt_zero";
       
   693 
       
   694 Goalw [real_zero_def] " 0r < %#m";
       
   695 by (auto_tac (claset(),simpset() addsimps 
       
   696     [real_preal_def,real_less_def,real_minus]));
       
   697 by (REPEAT(rtac exI 1));
       
   698 by (EVERY[rtac conjI 1, rtac conjI 2]);
       
   699 by (REPEAT(Blast_tac 2));
       
   700 by (full_simp_tac (simpset() addsimps 
       
   701   [preal_self_less_add_right] @ preal_add_ac) 1);
       
   702 qed "real_preal_zero_less";
       
   703 
       
   704 Goal "~ %#m < 0r";
       
   705 by (cut_facts_tac [real_preal_zero_less] 1);
       
   706 by (blast_tac (claset() addDs [real_less_trans] 
       
   707                addEs [real_less_irrefl]) 1);
       
   708 qed "real_preal_not_less_zero";
       
   709 
       
   710 Goal "0r < %~ %~ %#m";
       
   711 by (simp_tac (simpset() addsimps 
       
   712     [real_preal_zero_less]) 1);
       
   713 qed "real_minus_minus_zero_less";
       
   714 
       
   715 (* another lemma *)
       
   716 Goalw [real_zero_def] " 0r < %#m + %#m1";
       
   717 by (auto_tac (claset(),simpset() addsimps 
       
   718     [real_preal_def,real_less_def,real_add]));
       
   719 by (REPEAT(rtac exI 1));
       
   720 by (EVERY[rtac conjI 1, rtac conjI 2]);
       
   721 by (REPEAT(Blast_tac 2));
       
   722 by (full_simp_tac (simpset() addsimps preal_add_ac) 1);
       
   723 by (full_simp_tac (simpset() addsimps [preal_self_less_add_right,
       
   724     preal_add_assoc RS sym]) 1);
       
   725 qed "real_preal_sum_zero_less";
       
   726 
       
   727 Goal "%~ %#m < %#m1";
       
   728 by (auto_tac (claset(),simpset() addsimps 
       
   729     [real_preal_def,real_less_def,real_minus]));
       
   730 by (REPEAT(rtac exI 1));
       
   731 by (EVERY[rtac conjI 1, rtac conjI 2]);
       
   732 by (REPEAT(Blast_tac 2));
       
   733 by (full_simp_tac (simpset() addsimps preal_add_ac) 1);
       
   734 by (full_simp_tac (simpset() addsimps [preal_self_less_add_right,
       
   735     preal_add_assoc RS sym]) 1);
       
   736 qed "real_preal_minus_less_all";
       
   737 
       
   738 Goal "~ %#m < %~ %#m1";
       
   739 by (cut_facts_tac [real_preal_minus_less_all] 1);
       
   740 by (blast_tac (claset() addDs [real_less_trans] 
       
   741                addEs [real_less_irrefl]) 1);
       
   742 qed "real_preal_not_minus_gt_all";
       
   743 
       
   744 Goal "%~ %#m1 < %~ %#m2 ==> %#m2 < %#m1";
       
   745 by (auto_tac (claset(),simpset() addsimps 
       
   746     [real_preal_def,real_less_def,real_minus]));
       
   747 by (REPEAT(rtac exI 1));
       
   748 by (EVERY[rtac conjI 1, rtac conjI 2]);
       
   749 by (REPEAT(Blast_tac 2));
       
   750 by (auto_tac (claset(),simpset() addsimps preal_add_ac));
       
   751 by (asm_full_simp_tac (simpset() addsimps [preal_add_assoc RS sym]) 1);
       
   752 by (auto_tac (claset(),simpset() addsimps preal_add_ac));
       
   753 qed "real_preal_minus_less_rev1";
       
   754 
       
   755 Goal "%#m1 < %#m2 ==> %~ %#m2 < %~ %#m1";
       
   756 by (auto_tac (claset(),simpset() addsimps 
       
   757     [real_preal_def,real_less_def,real_minus]));
       
   758 by (REPEAT(rtac exI 1));
       
   759 by (EVERY[rtac conjI 1, rtac conjI 2]);
       
   760 by (REPEAT(Blast_tac 2));
       
   761 by (auto_tac (claset(),simpset() addsimps preal_add_ac));
       
   762 by (asm_full_simp_tac (simpset() addsimps [preal_add_assoc RS sym]) 1);
       
   763 by (auto_tac (claset(),simpset() addsimps preal_add_ac));
       
   764 qed "real_preal_minus_less_rev2";
       
   765 
       
   766 Goal "(%~ %#m1 < %~ %#m2) = (%#m2 < %#m1)";
       
   767 by (blast_tac (claset() addSIs [real_preal_minus_less_rev1,
       
   768                real_preal_minus_less_rev2]) 1);
       
   769 qed "real_preal_minus_less_rev_iff";
       
   770 
       
   771 Addsimps [real_preal_minus_less_rev_iff];
       
   772 
       
   773 (*** linearity ***)
       
   774 Goal "(R1::real) < R2 | R1 = R2 | R2 < R1";
       
   775 by (res_inst_tac [("x","R1")]  real_preal_trichotomyE 1);
       
   776 by (ALLGOALS(res_inst_tac [("x","R2")]  real_preal_trichotomyE));
       
   777 by (auto_tac (claset() addSDs [preal_le_anti_sym],
       
   778               simpset() addsimps [preal_less_le_iff,real_preal_minus_less_zero,
       
   779                real_preal_zero_less,real_preal_minus_less_all]));
       
   780 qed "real_linear";
       
   781 
       
   782 Goal "!!(R1::real). [| R1 < R2 ==> P;  R1 = R2 ==> P; \
       
   783 \                      R2 < R1 ==> P |] ==> P";
       
   784 by (cut_inst_tac [("R1.0","R1"),("R2.0","R2")] real_linear 1);
       
   785 by Auto_tac;
       
   786 qed "real_linear_less2";
       
   787 
       
   788 (*** Properties of <= ***)
       
   789 
       
   790 Goalw [real_le_def] "~(w < z) ==> z <= (w::real)";
       
   791 by (assume_tac 1);
       
   792 qed "real_leI";
       
   793 
       
   794 Goalw [real_le_def] "z<=w ==> ~(w<(z::real))";
       
   795 by (assume_tac 1);
       
   796 qed "real_leD";
       
   797 
       
   798 val real_leE = make_elim real_leD;
       
   799 
       
   800 Goal "(~(w < z)) = (z <= (w::real))";
       
   801 by (blast_tac (claset() addSIs [real_leI,real_leD]) 1);
       
   802 qed "real_less_le_iff";
       
   803 
       
   804 Goalw [real_le_def] "~ z <= w ==> w<(z::real)";
       
   805 by (Blast_tac 1);
       
   806 qed "not_real_leE";
       
   807 
       
   808 Goalw [real_le_def] "z < w ==> z <= (w::real)";
       
   809 by (blast_tac (claset() addEs [real_less_asym]) 1);
       
   810 qed "real_less_imp_le";
       
   811 
       
   812 Goalw [real_le_def] "!!(x::real). x <= y ==> x < y | x = y";
       
   813 by (cut_facts_tac [real_linear] 1);
       
   814 by (blast_tac (claset() addEs [real_less_irrefl,real_less_asym]) 1);
       
   815 qed "real_le_imp_less_or_eq";
       
   816 
       
   817 Goalw [real_le_def] "z<w | z=w ==> z <=(w::real)";
       
   818 by (cut_facts_tac [real_linear] 1);
       
   819 by (fast_tac (claset() addEs [real_less_irrefl,real_less_asym]) 1);
       
   820 qed "real_less_or_eq_imp_le";
       
   821 
       
   822 Goal "(x <= (y::real)) = (x < y | x=y)";
       
   823 by (REPEAT(ares_tac [iffI, real_less_or_eq_imp_le, real_le_imp_less_or_eq] 1));
       
   824 qed "real_le_eq_less_or_eq";
       
   825 
       
   826 Goal "w <= (w::real)";
       
   827 by (simp_tac (simpset() addsimps [real_le_eq_less_or_eq]) 1);
       
   828 qed "real_le_refl";
       
   829 
       
   830 val prems = goal Real.thy "!!i. [| i <= j; j < k |] ==> i < (k::real)";
       
   831 by (dtac real_le_imp_less_or_eq 1);
       
   832 by (blast_tac (claset() addIs [real_less_trans]) 1);
       
   833 qed "real_le_less_trans";
       
   834 
       
   835 Goal "!! (i::real). [| i < j; j <= k |] ==> i < k";
       
   836 by (dtac real_le_imp_less_or_eq 1);
       
   837 by (blast_tac (claset() addIs [real_less_trans]) 1);
       
   838 qed "real_less_le_trans";
       
   839 
       
   840 Goal "[| i <= j; j <= k |] ==> i <= (k::real)";
       
   841 by (EVERY1 [dtac real_le_imp_less_or_eq, dtac real_le_imp_less_or_eq,
       
   842             rtac real_less_or_eq_imp_le, blast_tac (claset() addIs [real_less_trans])]);
       
   843 qed "real_le_trans";
       
   844 
       
   845 Goal "[| z <= w; w <= z |] ==> z = (w::real)";
       
   846 by (EVERY1 [dtac real_le_imp_less_or_eq, dtac real_le_imp_less_or_eq,
       
   847             fast_tac (claset() addEs [real_less_irrefl,real_less_asym])]);
       
   848 qed "real_le_anti_sym";
       
   849 
       
   850 Goal "[| ~ y < x; y ~= x |] ==> x < (y::real)";
       
   851 by (rtac not_real_leE 1);
       
   852 by (blast_tac (claset() addDs [real_le_imp_less_or_eq]) 1);
       
   853 qed "not_less_not_eq_real_less";
       
   854 
       
   855 Goal "(0r < %~R) = (R < 0r)";
       
   856 by (res_inst_tac [("x","R")]  real_preal_trichotomyE 1);
       
   857 by (auto_tac (claset(),simpset() addsimps [real_preal_not_minus_gt_zero,
       
   858                         real_preal_not_less_zero,real_preal_zero_less,
       
   859                         real_preal_minus_less_zero]));
       
   860 qed "real_minus_zero_less_iff";
       
   861 
       
   862 Addsimps [real_minus_zero_less_iff];
       
   863 
       
   864 Goal "(%~R < 0r) = (0r < R)";
       
   865 by (res_inst_tac [("x","R")]  real_preal_trichotomyE 1);
       
   866 by (auto_tac (claset(),simpset() addsimps [real_preal_not_minus_gt_zero,
       
   867                         real_preal_not_less_zero,real_preal_zero_less,
       
   868                         real_preal_minus_less_zero]));
       
   869 qed "real_minus_zero_less_iff2";
       
   870 
    10 
   871 (** lemma **)
    11 (** lemma **)
   872 Goal "(0r < x) = (? y. x = %#y)";
    12 Goal "(0r < x) = (? y. x = %#y)";
   873 by (auto_tac (claset(),simpset() addsimps [real_preal_zero_less]));
    13 by (auto_tac (claset(),simpset() addsimps [real_preal_zero_less]));
   874 by (cut_inst_tac [("x","x")] real_preal_trichotomy 1);
    14 by (cut_inst_tac [("x","x")] real_preal_trichotomy 1);
   894 
    34 
   895 Goal "~ 0r < y ==> !x. y < %#x";
    35 Goal "~ 0r < y ==> !x. y < %#x";
   896 by (blast_tac (claset() addSIs [real_less_all_preal,real_leI]) 1);
    36 by (blast_tac (claset() addSIs [real_less_all_preal,real_leI]) 1);
   897 qed "real_less_all_real2";
    37 qed "real_less_all_real2";
   898 
    38 
   899 (**** Derive alternative definition for real_less ****)
    39 Goal "((x::real) < y) = (-y < -x)";
   900 (** lemma **)
       
   901 Goal "!!(R::real). ? A. S + A = R";
       
   902 by (res_inst_tac [("x","%~S + R")] exI 1);
       
   903 by (simp_tac (simpset() addsimps [real_add_minus,
       
   904     real_add_zero_right] @ real_add_ac) 1);
       
   905 qed "real_lemma_add_left_ex";
       
   906 
       
   907 Goal "!!(R::real). R < S ==> ? T. R + T = S";
       
   908 by (res_inst_tac [("x","R")]  real_preal_trichotomyE 1);
       
   909 by (ALLGOALS(res_inst_tac [("x","S")]  real_preal_trichotomyE));
       
   910 by (auto_tac (claset() addSDs [preal_le_anti_sym] addSDs [preal_less_add_left_Ex],
       
   911               simpset() addsimps [preal_less_le_iff,real_preal_add,real_minus_add_eq,
       
   912                real_preal_minus_less_zero,real_less_not_refl,real_minus_ex,real_add_assoc,
       
   913                real_preal_zero_less,real_preal_minus_less_all,real_add_minus_left,
       
   914                real_preal_not_less_zero,real_add_zero_left,real_lemma_add_left_ex]));
       
   915 qed "real_less_add_left_Ex";
       
   916 
       
   917 Goal "!!(R::real). R < S ==> ? T. 0r < T & R + T = S";
       
   918 by (res_inst_tac [("x","R")]  real_preal_trichotomyE 1);
       
   919 by (ALLGOALS(res_inst_tac [("x","S")]  real_preal_trichotomyE));
       
   920 by (auto_tac (claset() addSDs [preal_less_add_left_Ex],
       
   921                          simpset() addsimps [real_preal_not_minus_gt_all,
       
   922             real_preal_add, real_preal_not_less_zero,real_less_not_refl,
       
   923     real_preal_not_minus_gt_zero,real_add_zero_left,real_minus_add_eq]));
       
   924 by (res_inst_tac [("x","%#D")] exI 1);
       
   925 by (res_inst_tac [("x","%#m+%#ma")] exI 2);
       
   926 by (res_inst_tac [("x","%#m")] exI 3);
       
   927 by (res_inst_tac [("x","%#D")] exI 4);
       
   928 by (auto_tac (claset(),simpset() addsimps [real_preal_zero_less,
       
   929     real_preal_sum_zero_less,real_add_minus_left,real_add_assoc,
       
   930                           real_add_minus,real_add_zero_right]));
       
   931 by (simp_tac (simpset() addsimps [real_add_assoc RS sym, 
       
   932             real_add_minus_left,real_add_zero_left]) 1);
       
   933 qed "real_less_add_positive_left_Ex";
       
   934 
       
   935 (* lemmas *)
       
   936 (** change naff name(s)! **)
       
   937 Goal "(W < S) ==> (0r < S + %~W)";
       
   938 by (dtac real_less_add_positive_left_Ex 1);
       
   939 by (auto_tac (claset(),simpset() addsimps [real_add_minus,
       
   940     real_add_zero_right] @ real_add_ac));
       
   941 qed "real_less_sum_gt_zero";
       
   942 
       
   943 Goal "!!S. T = S + W ==> S = T + %~W";
       
   944 by (asm_simp_tac (simpset() addsimps [real_add_minus, real_add_zero_right] 
       
   945 		                     @ real_add_ac) 1);
       
   946 qed "real_lemma_change_eq_subj";
       
   947 
       
   948 (* FIXME: long! *)
       
   949 Goal "(0r < S + %~W) ==> (W < S)";
       
   950 by (rtac ccontr 1);
       
   951 by (dtac (real_leI RS real_le_imp_less_or_eq) 1);
       
   952 by (auto_tac (claset(),
       
   953     simpset() addsimps [real_less_not_refl,real_add_minus]));
       
   954 by (EVERY1[dtac real_less_add_positive_left_Ex, etac exE, etac conjE]);
       
   955 by (asm_full_simp_tac (simpset() addsimps [real_add_zero_left]) 1);
       
   956 by (dtac real_lemma_change_eq_subj 1);
       
   957 by (auto_tac (claset(),simpset() addsimps [real_minus_minus]));
       
   958 by (dtac real_less_sum_gt_zero 1);
       
   959 by (asm_full_simp_tac (simpset() addsimps [real_minus_add_eq] @ real_add_ac) 1);
       
   960 by (EVERY1[rotate_tac 1, dtac (real_add_left_commute RS ssubst)]);
       
   961 by (auto_tac (claset() addEs [real_less_asym],
       
   962               simpset() addsimps [real_add_minus,real_add_zero_right]));
       
   963 qed "real_sum_gt_zero_less";
       
   964 
       
   965 Goal "(0r < S + %~W) = (W < S)";
       
   966 by (blast_tac (claset() addIs [real_less_sum_gt_zero,
       
   967     real_sum_gt_zero_less]) 1);
       
   968 qed "real_less_sum_gt_0_iff";
       
   969 
       
   970 Goal "((x::real) < y) = (%~y < %~x)";
       
   971 by (rtac (real_less_sum_gt_0_iff RS subst) 1);
    40 by (rtac (real_less_sum_gt_0_iff RS subst) 1);
   972 by (res_inst_tac [("W1","x")] (real_less_sum_gt_0_iff RS subst) 1);
    41 by (res_inst_tac [("W1","x")] (real_less_sum_gt_0_iff RS subst) 1);
   973 by (simp_tac (simpset() addsimps [real_add_commute]) 1);
    42 by (simp_tac (simpset() addsimps [real_add_commute]) 1);
   974 qed "real_less_swap_iff";
    43 qed "real_less_swap_iff";
   975 
    44 
   976 Goal "[| R + L = S; 0r < L |] ==> R < S";
    45 Goal "[| R + L = S; 0r < L |] ==> R < S";
   977 by (rtac (real_less_sum_gt_0_iff RS iffD1) 1);
    46 by (rtac (real_less_sum_gt_0_iff RS iffD1) 1);
   978 by (auto_tac (claset(),simpset() addsimps [
    47 by (auto_tac (claset(), simpset() addsimps real_add_ac));
   979     real_add_minus,real_add_zero_right] @ real_add_ac));
       
   980 qed "real_lemma_add_positive_imp_less";
    48 qed "real_lemma_add_positive_imp_less";
   981 
    49 
   982 Goal "!!(R::real). ? T. 0r < T & R + T = S ==> R < S";
    50 Goal "!!(R::real). ? T. 0r < T & R + T = S ==> R < S";
   983 by (blast_tac (claset() addIs [real_lemma_add_positive_imp_less]) 1);
    51 by (blast_tac (claset() addIs [real_lemma_add_positive_imp_less]) 1);
   984 qed "real_ex_add_positive_left_less";
    52 qed "real_ex_add_positive_left_less";
   985 
    53 
   986 (*** alternative definition for real_less ***)
    54 (*Alternative definition for real_less.  NOT for rewriting*)
   987 Goal "!!(R::real). (? T. 0r < T & R + T = S) = (R < S)";
    55 Goal "!!(R::real). (R < S) = (? T. 0r < T & R + T = S)";
   988 by (blast_tac (claset() addSIs [real_less_add_positive_left_Ex,
    56 by (blast_tac (claset() addSIs [real_less_add_positive_left_Ex,
   989     real_ex_add_positive_left_less]) 1);
    57 				real_ex_add_positive_left_less]) 1);
   990 qed "real_less_iffdef";
    58 qed "real_less_iff_add";
   991 
    59 
   992 Goal "(0r < x) = (%~x < x)";
    60 Goal "(0r < x) = (-x < x)";
   993 by Safe_tac;
    61 by Safe_tac;
   994 by (rtac ccontr 2 THEN forward_tac 
    62 by (rtac ccontr 2 THEN forward_tac 
   995     [real_leI RS real_le_imp_less_or_eq] 2);
    63     [real_leI RS real_le_imp_less_or_eq] 2);
   996 by (Step_tac 2);
    64 by (Step_tac 2);
   997 by (dtac (real_minus_zero_less_iff RS iffD2) 2);
    65 by (dtac (real_minus_zero_less_iff RS iffD2) 2);
   998 by (blast_tac (claset() addIs [real_less_trans]) 2);
    66 by (blast_tac (claset() addIs [real_less_trans]) 2);
   999 by (auto_tac (claset(),simpset() addsimps 
    67 by (auto_tac (claset(),
  1000     [real_gt_zero_preal_Ex,real_preal_minus_less_self]));
    68 	      simpset() addsimps 
       
    69 	      [real_gt_zero_preal_Ex,real_preal_minus_less_self]));
  1001 qed "real_gt_zero_iff";
    70 qed "real_gt_zero_iff";
  1002 
    71 
  1003 Goal "(x < 0r) = (x < %~x)";
    72 Goal "(x < 0r) = (x < -x)";
  1004 by (rtac (real_minus_zero_less_iff RS subst) 1);
    73 by (rtac (real_minus_zero_less_iff RS subst) 1);
  1005 by (stac real_gt_zero_iff 1);
    74 by (stac real_gt_zero_iff 1);
  1006 by (Full_simp_tac 1);
    75 by (Full_simp_tac 1);
  1007 qed "real_lt_zero_iff";
    76 qed "real_lt_zero_iff";
  1008 
    77 
  1009 Goalw [real_le_def] "(0r <= x) = (%~x <= x)";
    78 Goalw [real_le_def] "(0r <= x) = (-x <= x)";
  1010 by (auto_tac (claset(),simpset() addsimps [real_lt_zero_iff RS sym]));
    79 by (auto_tac (claset(),simpset() addsimps [real_lt_zero_iff RS sym]));
  1011 qed "real_ge_zero_iff";
    80 qed "real_ge_zero_iff";
  1012 
    81 
  1013 Goalw [real_le_def] "(x <= 0r) = (x <= %~x)";
    82 Goalw [real_le_def] "(x <= 0r) = (x <= -x)";
  1014 by (auto_tac (claset(),simpset() addsimps [real_gt_zero_iff RS sym]));
    83 by (auto_tac (claset(),simpset() addsimps [real_gt_zero_iff RS sym]));
  1015 qed "real_le_zero_iff";
    84 qed "real_le_zero_iff";
  1016 
    85 
  1017 Goal "(%#m1 <= %#m2) = (m1 <= m2)";
    86 Goal "(%#m1 <= %#m2) = (m1 <= m2)";
  1018 by (auto_tac (claset() addSIs [preal_leI],
    87 by (auto_tac (claset() addSIs [preal_leI],
  1033 by (Asm_full_simp_tac 1);
   102 by (Asm_full_simp_tac 1);
  1034 qed "real_mult_less_zero1";
   103 qed "real_mult_less_zero1";
  1035 
   104 
  1036 Goal "!!(x::real). [| 0r <= x; 0r <= y |] ==> 0r <= x * y";
   105 Goal "!!(x::real). [| 0r <= x; 0r <= y |] ==> 0r <= x * y";
  1037 by (REPEAT(dtac real_le_imp_less_or_eq 1));
   106 by (REPEAT(dtac real_le_imp_less_or_eq 1));
  1038 by (auto_tac (claset() addIs [real_mult_order,
   107 by (auto_tac (claset() addIs [real_mult_order, real_less_imp_le],
  1039     real_less_imp_le],simpset() addsimps [real_le_refl]));
   108 	      simpset()));
  1040 qed "real_le_mult_order";
   109 qed "real_le_mult_order";
  1041 
   110 
  1042 Goal "!!(x::real). [| x <= 0r; y <= 0r |] ==> 0r <= x * y";
   111 Goal "!!(x::real). [| x <= 0r; y <= 0r |] ==> 0r <= x * y";
  1043 by (rtac real_less_or_eq_imp_le 1);
   112 by (rtac real_less_or_eq_imp_le 1);
  1044 by (dtac real_le_imp_less_or_eq 1 THEN etac disjE 1);
   113 by (dtac real_le_imp_less_or_eq 1 THEN etac disjE 1);
  1123 by (Blast_tac 1);
   192 by (Blast_tac 1);
  1124 by (Blast_tac 1);
   193 by (Blast_tac 1);
  1125 by (Blast_tac 1);
   194 by (Blast_tac 1);
  1126 qed "posreal_complete";
   195 qed "posreal_complete";
  1127 
   196 
  1128 (*------------------------------------------------------------------
   197 
  1129 
   198 
  1130  ------------------------------------------------------------------*)
   199 (*** Monotonicity results ***)
  1131 
   200 
  1132 Goal "!!(A::real). A < B ==> A + C < B + C";
   201 Goal "(v+z < w+z) = (v < (w::real))";
  1133 by (dtac (real_less_iffdef RS iffD2) 1);
   202 by (Simp_tac 1);
  1134 by (rtac (real_less_iffdef RS iffD1) 1);
   203 qed "real_add_right_cancel_less";
  1135 by (REPEAT(Step_tac 1));
   204 
  1136 by (full_simp_tac (simpset() addsimps real_add_ac) 1);
   205 Goal "(z+v < z+w) = (v < (w::real))";
  1137 qed "real_add_less_mono1";
   206 by (Simp_tac 1);
       
   207 qed "real_add_left_cancel_less";
       
   208 
       
   209 Addsimps [real_add_right_cancel_less, real_add_left_cancel_less];
       
   210 
       
   211 Goal "(v+z <= w+z) = (v <= (w::real))";
       
   212 by (Simp_tac 1);
       
   213 qed "real_add_right_cancel_le";
       
   214 
       
   215 Goal "(z+v <= z+w) = (v <= (w::real))";
       
   216 by (Simp_tac 1);
       
   217 qed "real_add_left_cancel_le";
       
   218 
       
   219 Addsimps [real_add_right_cancel_le, real_add_left_cancel_le];
       
   220 
       
   221 (*"v<=w ==> v+z <= w+z"*)
       
   222 bind_thm ("real_add_less_mono1", real_add_right_cancel_less RS iffD2);
       
   223 
       
   224 (*"v<=w ==> v+z <= w+z"*)
       
   225 bind_thm ("real_add_le_mono1", real_add_right_cancel_le RS iffD2);
       
   226 
       
   227 Goal "!!z z'::real. [| w'<w; z'<=z |] ==> w' + z' < w + z";
       
   228 by (etac (real_add_less_mono1 RS real_less_le_trans) 1);
       
   229 by (Simp_tac 1);
       
   230 qed "real_add_less_mono";
       
   231 
  1138 
   232 
  1139 Goal "!!(A::real). A < B ==> C + A < C + B";
   233 Goal "!!(A::real). A < B ==> C + A < C + B";
  1140 by (auto_tac (claset() addIs [real_add_less_mono1],
   234 by (Simp_tac 1);
  1141     simpset() addsimps [real_add_commute]));
       
  1142 qed "real_add_less_mono2";
   235 qed "real_add_less_mono2";
  1143 
   236 
  1144 Goal "!!(A::real). A + C < B + C ==> A < B";
   237 Goal "!!(A::real). A + C < B + C ==> A < B";
  1145 by (dres_inst_tac [("C","%~C")] real_add_less_mono1 1);
   238 by (Full_simp_tac 1);
  1146 by (asm_full_simp_tac (simpset() addsimps [real_add_assoc,
       
  1147     real_add_minus,real_add_zero_right]) 1);
       
  1148 qed "real_less_add_right_cancel";
   239 qed "real_less_add_right_cancel";
  1149 
   240 
  1150 Goal "!!(A::real). C + A < C + B ==> A < B";
   241 Goal "!!(A::real). C + A < C + B ==> A < B";
  1151 by (dres_inst_tac [("C","%~C")] real_add_less_mono2 1);
   242 by (Full_simp_tac 1);
  1152 by (asm_full_simp_tac (simpset() addsimps [real_add_assoc RS sym,
       
  1153     real_add_minus_left,real_add_zero_left]) 1);
       
  1154 qed "real_less_add_left_cancel";
   243 qed "real_less_add_left_cancel";
  1155 
   244 
  1156 Goal "[| 0r < x; 0r < y |] ==> 0r < x + y";
   245 Goal "[| 0r < x; 0r < y |] ==> 0r < x + y";
  1157 by (REPEAT(dtac (real_gt_zero_preal_Ex RS iffD1) 1));
   246 be real_less_trans 1;
  1158 by (rtac (real_gt_zero_preal_Ex RS iffD2) 1);
   247 bd real_add_less_mono2 1;
  1159 by (Step_tac 1);
   248 by (Full_simp_tac 1);
  1160 by (res_inst_tac [("x","y + ya")] exI 1);
       
  1161 by (full_simp_tac (simpset() addsimps [real_preal_add]) 1);
       
  1162 qed "real_add_order";
   249 qed "real_add_order";
  1163 
   250 
  1164 Goal "!!(x::real). [| 0r <= x; 0r <= y |] ==> 0r <= x + y";
   251 Goal "!!(x::real). [| 0r <= x; 0r <= y |] ==> 0r <= x + y";
  1165 by (REPEAT(dtac real_le_imp_less_or_eq 1));
   252 by (REPEAT(dtac real_le_imp_less_or_eq 1));
  1166 by (auto_tac (claset() addIs [real_add_order,
   253 by (auto_tac (claset() addIs [real_add_order, real_less_imp_le],
  1167     real_less_imp_le],simpset() addsimps [real_add_zero_left,
   254 	      simpset()));
  1168     real_add_zero_right,real_le_refl]));
       
  1169 qed "real_le_add_order";
   255 qed "real_le_add_order";
  1170 
   256 
  1171 Goal 
   257 Goal "[| R1 < S1; R2 < S2 |] ==> R1 + R2 < S1 + (S2::real)";
  1172       "[| R1 < S1; R2 < S2 |] ==> R1 + R2 < S1 + (S2::real)";
   258 bd real_add_less_mono1 1;
  1173 by (dtac (real_less_iffdef RS iffD2) 1);
   259 be real_less_trans 1;
  1174 by (dtac (real_less_iffdef RS iffD2) 1);
   260 be real_add_less_mono2 1;
  1175 by (rtac (real_less_iffdef RS iffD1) 1);
       
  1176 by Auto_tac;
       
  1177 by (res_inst_tac [("x","T + Ta")] exI 1);
       
  1178 by (auto_tac (claset(),simpset() addsimps [real_add_order] @ real_add_ac));
       
  1179 qed "real_add_less_mono";
   261 qed "real_add_less_mono";
  1180 
   262 
  1181 Goal "!!(x::real). [| 0r <= x; 0r <= y |] ==> 0r <= x + y";
       
  1182 by (REPEAT(dtac real_le_imp_less_or_eq 1));
       
  1183 by (auto_tac (claset() addIs [real_add_order,
       
  1184     real_less_imp_le],simpset() addsimps [real_add_zero_left,
       
  1185     real_add_zero_right,real_le_refl]));
       
  1186 qed "real_le_add_order";
       
  1187 
       
  1188 Goal "!!(q1::real). q1 <= q2  ==> x + q1 <= x + q2";
   263 Goal "!!(q1::real). q1 <= q2  ==> x + q1 <= x + q2";
  1189 by (dtac real_le_imp_less_or_eq 1);
   264 by (Simp_tac 1);
  1190 by (Step_tac 1);
       
  1191 by (auto_tac (claset() addSIs [real_le_refl,
       
  1192     real_less_imp_le,real_add_less_mono1],
       
  1193     simpset() addsimps [real_add_commute]));
       
  1194 qed "real_add_left_le_mono1";
   265 qed "real_add_left_le_mono1";
  1195 
   266 
  1196 Goal "!!(q1::real). q1 <= q2  ==> q1 + x <= q2 + x";
   267 Goal "[|i<=j;  k<=l |] ==> i + k <= j + (l::real)";
  1197 by (auto_tac (claset() addDs [real_add_left_le_mono1],
   268 bd real_add_le_mono1 1;
  1198     simpset() addsimps [real_add_commute]));
   269 be real_le_trans 1;
  1199 qed "real_add_le_mono1";
   270 by (Simp_tac 1);
  1200 
       
  1201 Goal "!!k l::real. [|i<=j;  k<=l |] ==> i + k <= j + l";
       
  1202 by (etac (real_add_le_mono1 RS real_le_trans) 1);
       
  1203 by (simp_tac (simpset() addsimps [real_add_commute]) 1);
       
  1204 (*j moves to the end because it is free while k, l are bound*)
       
  1205 by (etac real_add_le_mono1 1);
       
  1206 qed "real_add_le_mono";
   271 qed "real_add_le_mono";
  1207 
   272 
  1208 Goal "EX (x::real). x < y";
   273 Goal "EX (x::real). x < y";
  1209 by (rtac (real_add_zero_right RS subst) 1);
   274 by (rtac (real_add_zero_right RS subst) 1);
  1210 by (res_inst_tac [("x","y + %~1r")] exI 1);
   275 by (res_inst_tac [("x","y + -1r")] exI 1);
  1211 by (auto_tac (claset() addSIs [real_add_less_mono2],
   276 by (auto_tac (claset() addSIs [real_add_less_mono2],
  1212     simpset() addsimps [real_minus_zero_less_iff2,
   277 	  simpset() addsimps [real_minus_zero_less_iff2, real_zero_less_one]));
  1213     real_zero_less_one]));
       
  1214 qed "real_less_Ex";
   278 qed "real_less_Ex";
       
   279 
  1215 (*---------------------------------------------------------------------------------
   280 (*---------------------------------------------------------------------------------
  1216              An embedding of the naturals in the reals
   281              An embedding of the naturals in the reals
  1217  ---------------------------------------------------------------------------------*)
   282  ---------------------------------------------------------------------------------*)
  1218 
   283 
  1219 Goalw [real_nat_def] "%%#0 = 1r";
   284 Goalw [real_nat_def] "%%#0 = 1r";
  1265 qed "real_nat_less_zero";
   330 qed "real_nat_less_zero";
  1266 
   331 
  1267 Goal "1r <= %%#n";
   332 Goal "1r <= %%#n";
  1268 by (simp_tac (simpset() addsimps [real_nat_one RS sym]) 1);
   333 by (simp_tac (simpset() addsimps [real_nat_one RS sym]) 1);
  1269 by (induct_tac "n" 1);
   334 by (induct_tac "n" 1);
  1270 by (auto_tac (claset(),simpset () 
   335 by (auto_tac (claset(),
  1271     addsimps [real_nat_Suc,real_le_refl,real_nat_one]));
   336 	      simpset () addsimps [real_nat_Suc,real_nat_one,
  1272 by (res_inst_tac [("t","1r")] (real_add_zero_left RS subst) 1);
   337 				   real_nat_less_zero, real_less_imp_le]));
  1273 by (rtac real_add_le_mono 1);
       
  1274 by (auto_tac (claset(),simpset () 
       
  1275     addsimps [real_le_refl,real_nat_less_zero,
       
  1276     real_less_imp_le,real_add_zero_left]));
       
  1277 qed "real_nat_less_one";
   338 qed "real_nat_less_one";
  1278 
   339 
  1279 Goal "rinv(%%#n) ~= 0r";
   340 Goal "rinv(%%#n) ~= 0r";
  1280 by (rtac ((real_nat_less_zero RS 
   341 by (rtac ((real_nat_less_zero RS 
  1281     real_not_refl2 RS not_sym) RS rinv_not_zero) 1);
   342     real_not_refl2 RS not_sym) RS rinv_not_zero) 1);
  1316 qed "real_add_self";
   377 qed "real_add_self";
  1317 
   378 
  1318 Goal "x < x + 1r";
   379 Goal "x < x + 1r";
  1319 by (rtac (real_less_sum_gt_0_iff RS iffD1) 1);
   380 by (rtac (real_less_sum_gt_0_iff RS iffD1) 1);
  1320 by (full_simp_tac (simpset() addsimps [real_zero_less_one,
   381 by (full_simp_tac (simpset() addsimps [real_zero_less_one,
  1321     real_add_assoc,real_add_minus,real_add_zero_right,
   382 				real_add_assoc, real_add_left_commute]) 1);
  1322     real_add_left_commute]) 1);
       
  1323 qed "real_self_less_add_one";
   383 qed "real_self_less_add_one";
  1324 
   384 
  1325 Goal "1r < 1r + 1r";
   385 Goal "1r < 1r + 1r";
  1326 by (rtac real_self_less_add_one 1);
   386 by (rtac real_self_less_add_one 1);
  1327 qed "real_one_less_two";
   387 qed "real_one_less_two";
  1328 
   388 
  1329 Goal "0r < 1r + 1r";
   389 Goal "0r < 1r + 1r";
  1330 by (rtac ([real_zero_less_one,
   390 by (rtac ([real_zero_less_one,
  1331           real_one_less_two] MRS real_less_trans) 1);
   391 	   real_one_less_two] MRS real_less_trans) 1);
  1332 qed "real_zero_less_two";
   392 qed "real_zero_less_two";
  1333 
   393 
  1334 Goal "1r + 1r ~= 0r";
   394 Goal "1r + 1r ~= 0r";
  1335 by (rtac (real_zero_less_two RS real_not_refl2 RS not_sym) 1);
   395 by (rtac (real_zero_less_two RS real_not_refl2 RS not_sym) 1);
  1336 qed "real_two_not_zero";
   396 qed "real_two_not_zero";
  1356 qed "real_mult_less_mono2";
   416 qed "real_mult_less_mono2";
  1357 
   417 
  1358 Goal "!!(x::real). [| 0r<z; x*z<y*z |] ==> x<y";
   418 Goal "!!(x::real). [| 0r<z; x*z<y*z |] ==> x<y";
  1359 by (forw_inst_tac [("x","x*z")] (real_rinv_gt_zero 
   419 by (forw_inst_tac [("x","x*z")] (real_rinv_gt_zero 
  1360                        RS real_mult_less_mono1) 1);
   420                        RS real_mult_less_mono1) 1);
  1361 by (auto_tac (claset(),simpset() addsimps 
   421 by (auto_tac (claset(),
       
   422 	      simpset() addsimps 
  1362      [real_mult_assoc,real_not_refl2 RS not_sym]));
   423      [real_mult_assoc,real_not_refl2 RS not_sym]));
  1363 qed "real_mult_less_cancel1";
   424 qed "real_mult_less_cancel1";
  1364 
   425 
  1365 Goal "!!(x::real). [| 0r<z; z*x<z*y |] ==> x<y";
   426 Goal "!!(x::real). [| 0r<z; z*x<z*y |] ==> x<y";
  1366 by (etac real_mult_less_cancel1 1);
   427 by (etac real_mult_less_cancel1 1);
  1388 by (asm_simp_tac (simpset() addsimps [real_mult_commute,real_mult_le_less_mono1]) 1);
   449 by (asm_simp_tac (simpset() addsimps [real_mult_commute,real_mult_le_less_mono1]) 1);
  1389 qed "real_mult_le_less_mono2";
   450 qed "real_mult_le_less_mono2";
  1390 
   451 
  1391 Goal "!!x y (z::real). [| 0r<=z; x<=y |] ==> z*x<=z*y";
   452 Goal "!!x y (z::real). [| 0r<=z; x<=y |] ==> z*x<=z*y";
  1392 by (dres_inst_tac [("x","x")] real_le_imp_less_or_eq 1);
   453 by (dres_inst_tac [("x","x")] real_le_imp_less_or_eq 1);
  1393 by (auto_tac (claset() addIs [real_mult_le_less_mono2,real_le_refl],simpset()));
   454 by (auto_tac (claset() addIs [real_mult_le_less_mono2], simpset()));
  1394 qed "real_mult_le_le_mono1";
   455 qed "real_mult_le_le_mono1";
  1395 
   456 
  1396 Goal "!!(x::real). x < y ==> x < (x + y)*rinv(1r + 1r)";
   457 Goal "!!(x::real). x < y ==> x < (x + y)*rinv(1r + 1r)";
  1397 by (dres_inst_tac [("C","x")] real_add_less_mono2 1);
   458 by (dres_inst_tac [("C","x")] real_add_less_mono2 1);
  1398 by (dtac (real_add_self RS subst) 1);
   459 by (dtac (real_add_self RS subst) 1);
  1400           real_mult_less_mono1) 1);
   461           real_mult_less_mono1) 1);
  1401 by (asm_full_simp_tac (simpset() addsimps [real_mult_assoc]) 1);
   462 by (asm_full_simp_tac (simpset() addsimps [real_mult_assoc]) 1);
  1402 qed "real_less_half_sum";
   463 qed "real_less_half_sum";
  1403 
   464 
  1404 Goal "!!(x::real). x < y ==> (x + y)*rinv(1r + 1r) < y";
   465 Goal "!!(x::real). x < y ==> (x + y)*rinv(1r + 1r) < y";
  1405 by (dres_inst_tac [("C","y")] real_add_less_mono1 1);
   466 by (dtac real_add_less_mono1 1);
  1406 by (dtac (real_add_self RS subst) 1);
   467 by (dtac (real_add_self RS subst) 1);
  1407 by (dtac (real_zero_less_two RS real_rinv_gt_zero RS 
   468 by (dtac (real_zero_less_two RS real_rinv_gt_zero RS 
  1408           real_mult_less_mono1) 1);
   469           real_mult_less_mono1) 1);
  1409 by (asm_full_simp_tac (simpset() addsimps [real_mult_assoc]) 1);
   470 by (asm_full_simp_tac (simpset() addsimps [real_mult_assoc]) 1);
  1410 qed "real_gt_half_sum";
   471 qed "real_gt_half_sum";
  1417 by (Step_tac 1);
   478 by (Step_tac 1);
  1418 by (dres_inst_tac [("n1","n")] (real_nat_less_zero 
   479 by (dres_inst_tac [("n1","n")] (real_nat_less_zero 
  1419                        RS real_mult_less_mono1) 1);
   480                        RS real_mult_less_mono1) 1);
  1420 by (dres_inst_tac [("n2","n")] (real_nat_less_zero RS 
   481 by (dres_inst_tac [("n2","n")] (real_nat_less_zero RS 
  1421         real_rinv_gt_zero RS real_mult_less_mono1) 2);
   482         real_rinv_gt_zero RS real_mult_less_mono1) 2);
  1422 by (auto_tac (claset(),simpset() addsimps [(real_nat_less_zero RS 
   483 by (auto_tac (claset(),
       
   484 	      simpset() addsimps [(real_nat_less_zero RS 
  1423     real_not_refl2 RS not_sym),real_mult_assoc]));
   485     real_not_refl2 RS not_sym),real_mult_assoc]));
  1424 qed "real_nat_rinv_Ex_iff";
   486 qed "real_nat_rinv_Ex_iff";
  1425 
   487 
  1426 Goalw [real_nat_def] "(%%#n < %%#m) = (n < m)";
   488 Goalw [real_nat_def] "(%%#n < %%#m) = (n < m)";
  1427 by Auto_tac;
   489 by Auto_tac;
  1433 by (Step_tac 1);
   495 by (Step_tac 1);
  1434 by (res_inst_tac [("n2","n")] (real_nat_less_zero RS 
   496 by (res_inst_tac [("n2","n")] (real_nat_less_zero RS 
  1435     real_rinv_gt_zero RS real_mult_less_cancel1) 1);
   497     real_rinv_gt_zero RS real_mult_less_cancel1) 1);
  1436 by (res_inst_tac [("x1","u")] ( real_rinv_gt_zero
   498 by (res_inst_tac [("x1","u")] ( real_rinv_gt_zero
  1437    RS real_mult_less_cancel1) 2);
   499    RS real_mult_less_cancel1) 2);
  1438 by (auto_tac (claset(),simpset() addsimps [real_nat_less_zero, 
   500 by (auto_tac (claset(),
       
   501 	      simpset() addsimps [real_nat_less_zero, 
  1439     real_not_refl2 RS not_sym]));
   502     real_not_refl2 RS not_sym]));
  1440 by (res_inst_tac [("z","u")] real_mult_less_cancel2 1);
   503 by (res_inst_tac [("z","u")] real_mult_less_cancel2 1);
  1441 by (res_inst_tac [("n1","n")] (real_nat_less_zero RS 
   504 by (res_inst_tac [("n1","n")] (real_nat_less_zero RS 
  1442     real_mult_less_cancel2) 3);
   505     real_mult_less_cancel2) 3);
  1443 by (auto_tac (claset(),simpset() addsimps [real_nat_less_zero, 
   506 by (auto_tac (claset(),
       
   507 	      simpset() addsimps [real_nat_less_zero, 
  1444     real_not_refl2 RS not_sym,real_mult_assoc RS sym]));
   508     real_not_refl2 RS not_sym,real_mult_assoc RS sym]));
  1445 qed "real_nat_less_rinv_iff";
   509 qed "real_nat_less_rinv_iff";
  1446 
   510 
  1447 Goal "0r < u ==> (u = rinv(%%#n)) = (%%#n = rinv u)";
   511 Goal "0r < u ==> (u = rinv(%%#n)) = (%%#n = rinv u)";
  1448 by (auto_tac (claset(),simpset() addsimps [real_rinv_rinv,
   512 by (auto_tac (claset(),
       
   513 	      simpset() addsimps [real_rinv_rinv,
  1449     real_nat_less_zero,real_not_refl2 RS not_sym]));
   514     real_nat_less_zero,real_not_refl2 RS not_sym]));
  1450 qed "real_nat_rinv_eq_iff";
   515 qed "real_nat_rinv_eq_iff";
  1451 
   516 
  1452 (*
   517 (*
  1453 (*------------------------------------------------------------------
   518 (*------------------------------------------------------------------
  1456 Goalw [real_ub_def] "[| real_ub u S; x : S |] ==> x <= u";
   521 Goalw [real_ub_def] "[| real_ub u S; x : S |] ==> x <= u";
  1457 by Auto_tac;
   522 by Auto_tac;
  1458 qed "real_ubD";
   523 qed "real_ubD";
  1459 
   524 
  1460 *)
   525 *)
       
   526 
       
   527