16 |
16 |
17 (** first half: equiv A r ==> r^-1 O r = r **) |
17 (** first half: equiv A r ==> r^-1 O r = r **) |
18 |
18 |
19 goalw Equiv.thy [trans_def,sym_def,inverse_def] |
19 goalw Equiv.thy [trans_def,sym_def,inverse_def] |
20 "!!r. [| sym(r); trans(r) |] ==> r^-1 O r <= r"; |
20 "!!r. [| sym(r); trans(r) |] ==> r^-1 O r <= r"; |
21 by (fast_tac (!claset addSEs [inverseD]) 1); |
21 by (blast_tac (!claset addSEs [inverseD]) 1); |
22 qed "sym_trans_comp_subset"; |
22 qed "sym_trans_comp_subset"; |
23 |
23 |
24 goalw Equiv.thy [refl_def] |
24 goalw Equiv.thy [refl_def] |
25 "!!A r. refl A r ==> r <= r^-1 O r"; |
25 "!!A r. refl A r ==> r <= r^-1 O r"; |
26 by (fast_tac (!claset addIs [compI]) 1); |
26 by (Blast_tac 1); |
27 qed "refl_comp_subset"; |
27 qed "refl_comp_subset"; |
28 |
28 |
29 goalw Equiv.thy [equiv_def] |
29 goalw Equiv.thy [equiv_def] |
30 "!!A r. equiv A r ==> r^-1 O r = r"; |
30 "!!A r. equiv A r ==> r^-1 O r = r"; |
|
31 by (Clarify_tac 1); |
31 by (rtac equalityI 1); |
32 by (rtac equalityI 1); |
32 by (REPEAT (ares_tac [sym_trans_comp_subset, refl_comp_subset] 1 |
33 by (REPEAT (ares_tac [sym_trans_comp_subset, refl_comp_subset] 1)); |
33 ORELSE etac conjE 1)); |
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34 qed "equiv_comp_eq"; |
34 qed "equiv_comp_eq"; |
35 |
35 |
36 (*second half*) |
36 (*second half*) |
37 goalw Equiv.thy [equiv_def,refl_def,sym_def,trans_def] |
37 goalw Equiv.thy [equiv_def,refl_def,sym_def,trans_def] |
38 "!!A r. [| r^-1 O r = r; Domain(r) = A |] ==> equiv A r"; |
38 "!!A r. [| r^-1 O r = r; Domain(r) = A |] ==> equiv A r"; |
39 by (etac equalityE 1); |
39 by (etac equalityE 1); |
40 by (subgoal_tac "ALL x y. (x,y) : r --> (y,x) : r" 1); |
40 by (subgoal_tac "ALL x y. (x,y) : r --> (y,x) : r" 1); |
41 by (Step_tac 1); |
41 by (ALLGOALS Fast_tac); |
42 by (fast_tac (!claset addIs [compI]) 3); |
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43 by (ALLGOALS (fast_tac (!claset addIs [compI]))); |
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44 qed "comp_equivI"; |
42 qed "comp_equivI"; |
45 |
43 |
46 (** Equivalence classes **) |
44 (** Equivalence classes **) |
47 |
45 |
48 (*Lemma for the next result*) |
46 (*Lemma for the next result*) |
49 goalw Equiv.thy [equiv_def,trans_def,sym_def] |
47 goalw Equiv.thy [equiv_def,trans_def,sym_def] |
50 "!!A r. [| equiv A r; (a,b): r |] ==> r^^{a} <= r^^{b}"; |
48 "!!A r. [| equiv A r; (a,b): r |] ==> r^^{a} <= r^^{b}"; |
51 by (Step_tac 1); |
49 by (Blast_tac 1); |
52 by (rtac ImageI 1); |
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53 by (Fast_tac 2); |
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54 by (Fast_tac 1); |
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55 qed "equiv_class_subset"; |
50 qed "equiv_class_subset"; |
56 |
51 |
57 goal Equiv.thy "!!A r. [| equiv A r; (a,b): r |] ==> r^^{a} = r^^{b}"; |
52 goal Equiv.thy "!!A r. [| equiv A r; (a,b): r |] ==> r^^{a} = r^^{b}"; |
58 by (REPEAT (ares_tac [equalityI, equiv_class_subset] 1)); |
53 by (REPEAT (ares_tac [equalityI, equiv_class_subset] 1)); |
59 by (rewrite_goals_tac [equiv_def,sym_def]); |
54 by (rewrite_goals_tac [equiv_def,sym_def]); |
60 by (Fast_tac 1); |
55 by (Blast_tac 1); |
61 qed "equiv_class_eq"; |
56 qed "equiv_class_eq"; |
62 |
57 |
63 goalw Equiv.thy [equiv_def,refl_def] |
58 goalw Equiv.thy [equiv_def,refl_def] |
64 "!!A r. [| equiv A r; a: A |] ==> a: r^^{a}"; |
59 "!!A r. [| equiv A r; a: A |] ==> a: r^^{a}"; |
65 by (Fast_tac 1); |
60 by (Blast_tac 1); |
66 qed "equiv_class_self"; |
61 qed "equiv_class_self"; |
67 |
62 |
68 (*Lemma for the next result*) |
63 (*Lemma for the next result*) |
69 goalw Equiv.thy [equiv_def,refl_def] |
64 goalw Equiv.thy [equiv_def,refl_def] |
70 "!!A r. [| equiv A r; r^^{b} <= r^^{a}; b: A |] ==> (a,b): r"; |
65 "!!A r. [| equiv A r; r^^{b} <= r^^{a}; b: A |] ==> (a,b): r"; |
71 by (Fast_tac 1); |
66 by (Blast_tac 1); |
72 qed "subset_equiv_class"; |
67 qed "subset_equiv_class"; |
73 |
68 |
74 goal Equiv.thy |
69 goal Equiv.thy |
75 "!!A r. [| r^^{a} = r^^{b}; equiv A r; b: A |] ==> (a,b): r"; |
70 "!!A r. [| r^^{a} = r^^{b}; equiv A r; b: A |] ==> (a,b): r"; |
76 by (REPEAT (ares_tac [equalityD2, subset_equiv_class] 1)); |
71 by (REPEAT (ares_tac [equalityD2, subset_equiv_class] 1)); |
77 qed "eq_equiv_class"; |
72 qed "eq_equiv_class"; |
78 |
73 |
79 (*thus r^^{a} = r^^{b} as well*) |
74 (*thus r^^{a} = r^^{b} as well*) |
80 goalw Equiv.thy [equiv_def,trans_def,sym_def] |
75 goalw Equiv.thy [equiv_def,trans_def,sym_def] |
81 "!!A r. [| equiv A r; x: (r^^{a} Int r^^{b}) |] ==> (a,b): r"; |
76 "!!A r. [| equiv A r; x: (r^^{a} Int r^^{b}) |] ==> (a,b): r"; |
82 by (Fast_tac 1); |
77 by (Blast_tac 1); |
83 qed "equiv_class_nondisjoint"; |
78 qed "equiv_class_nondisjoint"; |
84 |
79 |
85 val [major] = goalw Equiv.thy [equiv_def,refl_def] |
80 val [major] = goalw Equiv.thy [equiv_def,refl_def] |
86 "equiv A r ==> r <= A Times A"; |
81 "equiv A r ==> r <= A Times A"; |
87 by (rtac (major RS conjunct1 RS conjunct1) 1); |
82 by (rtac (major RS conjunct1 RS conjunct1) 1); |
88 qed "equiv_type"; |
83 qed "equiv_type"; |
89 |
84 |
90 goal Equiv.thy |
85 goal Equiv.thy |
91 "!!A r. equiv A r ==> ((x,y): r) = (r^^{x} = r^^{y} & x:A & y:A)"; |
86 "!!A r. equiv A r ==> ((x,y): r) = (r^^{x} = r^^{y} & x:A & y:A)"; |
92 by (Step_tac 1); |
87 by (blast_tac (!claset addSIs [equiv_class_eq] |
93 by ((rtac equiv_class_eq 1) THEN (assume_tac 1) THEN (assume_tac 1)); |
88 addDs [eq_equiv_class, equiv_type]) 1); |
94 by ((rtac eq_equiv_class 3) THEN |
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95 (assume_tac 4) THEN (assume_tac 4) THEN (assume_tac 3)); |
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96 by ((dtac equiv_type 1) THEN (dtac rev_subsetD 1) THEN |
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97 (assume_tac 1) THEN (dtac SigmaD1 1) THEN (assume_tac 1)); |
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98 by ((dtac equiv_type 1) THEN (dtac rev_subsetD 1) THEN |
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99 (assume_tac 1) THEN (dtac SigmaD2 1) THEN (assume_tac 1)); |
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100 qed "equiv_class_eq_iff"; |
89 qed "equiv_class_eq_iff"; |
101 |
90 |
102 goal Equiv.thy |
91 goal Equiv.thy |
103 "!!A r. [| equiv A r; x: A; y: A |] ==> (r^^{x} = r^^{y}) = ((x,y): r)"; |
92 "!!A r. [| equiv A r; x: A; y: A |] ==> (r^^{x} = r^^{y}) = ((x,y): r)"; |
104 by (Step_tac 1); |
93 by (blast_tac (!claset addSIs [equiv_class_eq] |
105 by ((rtac eq_equiv_class 1) THEN |
94 addDs [eq_equiv_class, equiv_type]) 1); |
106 (assume_tac 1) THEN (assume_tac 1) THEN (assume_tac 1)); |
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107 by ((rtac equiv_class_eq 1) THEN |
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108 (assume_tac 1) THEN (assume_tac 1)); |
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109 qed "eq_equiv_class_iff"; |
95 qed "eq_equiv_class_iff"; |
110 |
96 |
111 (*** Quotients ***) |
97 (*** Quotients ***) |
112 |
98 |
113 (** Introduction/elimination rules -- needed? **) |
99 (** Introduction/elimination rules -- needed? **) |
114 |
100 |
115 goalw Equiv.thy [quotient_def] "!!A. x:A ==> r^^{x}: A/r"; |
101 goalw Equiv.thy [quotient_def] "!!A. x:A ==> r^^{x}: A/r"; |
116 by (Fast_tac 1); |
102 by (Blast_tac 1); |
117 qed "quotientI"; |
103 qed "quotientI"; |
118 |
104 |
119 val [major,minor] = goalw Equiv.thy [quotient_def] |
105 val [major,minor] = goalw Equiv.thy [quotient_def] |
120 "[| X:(A/r); !!x. [| X = r^^{x}; x:A |] ==> P |] \ |
106 "[| X:(A/r); !!x. [| X = r^^{x}; x:A |] ==> P |] \ |
121 \ ==> P"; |
107 \ ==> P"; |
122 by (resolve_tac [major RS UN_E] 1); |
108 by (resolve_tac [major RS UN_E] 1); |
123 by (rtac minor 1); |
109 by (rtac minor 1); |
124 by (assume_tac 2); |
110 by (assume_tac 2); |
125 by (Fast_tac 1); |
111 by (Fast_tac 1); (*Blast_tac FAILS to prove it*) |
126 qed "quotientE"; |
112 qed "quotientE"; |
127 |
113 |
128 goalw Equiv.thy [equiv_def,refl_def,quotient_def] |
114 goalw Equiv.thy [equiv_def,refl_def,quotient_def] |
129 "!!A r. equiv A r ==> Union(A/r) = A"; |
115 "!!A r. equiv A r ==> Union(A/r) = A"; |
130 by (blast_tac (!claset addSIs [equalityI]) 1); |
116 by (blast_tac (!claset addSIs [equalityI]) 1); |
155 (*Conversion rule*) |
141 (*Conversion rule*) |
156 goal Equiv.thy "!!A r. [| equiv A r; congruent r b; a: A |] \ |
142 goal Equiv.thy "!!A r. [| equiv A r; congruent r b; a: A |] \ |
157 \ ==> (UN x:r^^{a}. b(x)) = b(a)"; |
143 \ ==> (UN x:r^^{a}. b(x)) = b(a)"; |
158 by (rtac (equiv_class_self RS UN_singleton) 1 THEN REPEAT (assume_tac 1)); |
144 by (rtac (equiv_class_self RS UN_singleton) 1 THEN REPEAT (assume_tac 1)); |
159 by (rewrite_goals_tac [equiv_def,congruent_def,sym_def]); |
145 by (rewrite_goals_tac [equiv_def,congruent_def,sym_def]); |
160 by (Fast_tac 1); |
146 by (Blast_tac 1); |
161 qed "UN_equiv_class"; |
147 qed "UN_equiv_class"; |
162 |
148 |
163 (*type checking of UN x:r``{a}. b(x) *) |
149 (*type checking of UN x:r``{a}. b(x) *) |
164 val prems = goalw Equiv.thy [quotient_def] |
150 val prems = goalw Equiv.thy [quotient_def] |
165 "[| equiv A r; congruent r b; X: A/r; \ |
151 "[| equiv A r; congruent r b; X: A/r; \ |
166 \ !!x. x : A ==> b(x) : B |] \ |
152 \ !!x. x : A ==> b(x) : B |] \ |
167 \ ==> (UN x:X. b(x)) : B"; |
153 \ ==> (UN x:X. b(x)) : B"; |
168 by (cut_facts_tac prems 1); |
154 by (cut_facts_tac prems 1); |
169 by (Step_tac 1); |
155 by (Clarify_tac 1); |
170 by (stac UN_equiv_class 1); |
156 by (stac UN_equiv_class 1); |
171 by (REPEAT (ares_tac prems 1)); |
157 by (REPEAT (ares_tac prems 1)); |
172 qed "UN_equiv_class_type"; |
158 qed "UN_equiv_class_type"; |
173 |
159 |
174 (*Sufficient conditions for injectiveness. Could weaken premises! |
160 (*Sufficient conditions for injectiveness. Could weaken premises! |
191 (**** Defining binary operations upon equivalence classes ****) |
177 (**** Defining binary operations upon equivalence classes ****) |
192 |
178 |
193 |
179 |
194 goalw Equiv.thy [congruent_def,congruent2_def,equiv_def,refl_def] |
180 goalw Equiv.thy [congruent_def,congruent2_def,equiv_def,refl_def] |
195 "!!A r. [| equiv A r; congruent2 r b; a: A |] ==> congruent r (b a)"; |
181 "!!A r. [| equiv A r; congruent2 r b; a: A |] ==> congruent r (b a)"; |
196 by (Fast_tac 1); |
182 by (Blast_tac 1); |
197 qed "congruent2_implies_congruent"; |
183 qed "congruent2_implies_congruent"; |
198 |
184 |
199 goalw Equiv.thy [congruent_def] |
185 goalw Equiv.thy [congruent_def] |
200 "!!A r. [| equiv A r; congruent2 r b; a: A |] ==> \ |
186 "!!A r. [| equiv A r; congruent2 r b; a: A |] ==> \ |
201 \ congruent r (%x1. UN x2:r^^{a}. b x1 x2)"; |
187 \ congruent r (%x1. UN x2:r^^{a}. b x1 x2)"; |
202 by (Step_tac 1); |
188 by (Clarify_tac 1); |
203 by (rtac (equiv_type RS subsetD RS SigmaE2) 1 THEN REPEAT (assume_tac 1)); |
189 by (rtac (equiv_type RS subsetD RS SigmaE2) 1 THEN REPEAT (assume_tac 1)); |
204 by (asm_simp_tac (!simpset addsimps [UN_equiv_class, |
190 by (asm_simp_tac (!simpset addsimps [UN_equiv_class, |
205 congruent2_implies_congruent]) 1); |
191 congruent2_implies_congruent]) 1); |
206 by (rewrite_goals_tac [congruent2_def,equiv_def,refl_def]); |
192 by (rewrite_goals_tac [congruent2_def,equiv_def,refl_def]); |
207 by (Fast_tac 1); |
193 by (Blast_tac 1); |
208 qed "congruent2_implies_congruent_UN"; |
194 qed "congruent2_implies_congruent_UN"; |
209 |
195 |
210 goal Equiv.thy |
196 goal Equiv.thy |
211 "!!A r. [| equiv A r; congruent2 r b; a1: A; a2: A |] \ |
197 "!!A r. [| equiv A r; congruent2 r b; a1: A; a2: A |] \ |
212 \ ==> (UN x1:r^^{a1}. UN x2:r^^{a2}. b x1 x2) = b a1 a2"; |
198 \ ==> (UN x1:r^^{a1}. UN x2:r^^{a2}. b x1 x2) = b a1 a2"; |