--- a/src/HOL/Library/Abstract_Rat.thy Wed Sep 07 11:36:39 2011 +0200
+++ b/src/HOL/Library/Abstract_Rat.thy Wed Sep 07 16:37:50 2011 +0200
@@ -10,64 +10,58 @@
type_synonym Num = "int \<times> int"
-abbreviation
- Num0_syn :: Num ("0\<^sub>N")
-where "0\<^sub>N \<equiv> (0, 0)"
+abbreviation Num0_syn :: Num ("0\<^sub>N")
+ where "0\<^sub>N \<equiv> (0, 0)"
-abbreviation
- Numi_syn :: "int \<Rightarrow> Num" ("_\<^sub>N")
-where "i\<^sub>N \<equiv> (i, 1)"
+abbreviation Numi_syn :: "int \<Rightarrow> Num" ("_\<^sub>N")
+ where "i\<^sub>N \<equiv> (i, 1)"
-definition
- isnormNum :: "Num \<Rightarrow> bool"
-where
+definition isnormNum :: "Num \<Rightarrow> bool" where
"isnormNum = (\<lambda>(a,b). (if a = 0 then b = 0 else b > 0 \<and> gcd a b = 1))"
-definition
- normNum :: "Num \<Rightarrow> Num"
-where
- "normNum = (\<lambda>(a,b). (if a=0 \<or> b = 0 then (0,0) else
- (let g = gcd a b
- in if b > 0 then (a div g, b div g) else (- (a div g), - (b div g)))))"
+definition normNum :: "Num \<Rightarrow> Num" where
+ "normNum = (\<lambda>(a,b).
+ (if a=0 \<or> b = 0 then (0,0) else
+ (let g = gcd a b
+ in if b > 0 then (a div g, b div g) else (- (a div g), - (b div g)))))"
-declare gcd_dvd1_int[presburger]
-declare gcd_dvd2_int[presburger]
+declare gcd_dvd1_int[presburger] gcd_dvd2_int[presburger]
+
lemma normNum_isnormNum [simp]: "isnormNum (normNum x)"
proof -
have " \<exists> a b. x = (a,b)" by auto
then obtain a b where x[simp]: "x = (a,b)" by blast
- {assume "a=0 \<or> b = 0" hence ?thesis by (simp add: normNum_def isnormNum_def)}
+ { assume "a=0 \<or> b = 0" hence ?thesis by (simp add: normNum_def isnormNum_def) }
moreover
- {assume anz: "a \<noteq> 0" and bnz: "b \<noteq> 0"
+ { assume anz: "a \<noteq> 0" and bnz: "b \<noteq> 0"
let ?g = "gcd a b"
let ?a' = "a div ?g"
let ?b' = "b div ?g"
let ?g' = "gcd ?a' ?b'"
- from anz bnz have "?g \<noteq> 0" by simp with gcd_ge_0_int[of a b]
+ from anz bnz have "?g \<noteq> 0" by simp with gcd_ge_0_int[of a b]
have gpos: "?g > 0" by arith
- have gdvd: "?g dvd a" "?g dvd b" by arith+
- from zdvd_mult_div_cancel[OF gdvd(1)] zdvd_mult_div_cancel[OF gdvd(2)]
- anz bnz
- have nz':"?a' \<noteq> 0" "?b' \<noteq> 0"
- by - (rule notI, simp)+
- from anz bnz have stupid: "a \<noteq> 0 \<or> b \<noteq> 0" by arith
+ have gdvd: "?g dvd a" "?g dvd b" by arith+
+ from zdvd_mult_div_cancel[OF gdvd(1)] zdvd_mult_div_cancel[OF gdvd(2)] anz bnz
+ have nz':"?a' \<noteq> 0" "?b' \<noteq> 0" by - (rule notI, simp)+
+ from anz bnz have stupid: "a \<noteq> 0 \<or> b \<noteq> 0" by arith
from div_gcd_coprime_int[OF stupid] have gp1: "?g' = 1" .
from bnz have "b < 0 \<or> b > 0" by arith
moreover
- {assume b: "b > 0"
- from b have "?b' \<ge> 0"
- by (presburger add: pos_imp_zdiv_nonneg_iff[OF gpos])
+ { assume b: "b > 0"
+ from b have "?b' \<ge> 0"
+ by (presburger add: pos_imp_zdiv_nonneg_iff[OF gpos])
with nz' have b': "?b' > 0" by arith
from b b' anz bnz nz' gp1 have ?thesis
- by (simp add: isnormNum_def normNum_def Let_def split_def fst_conv snd_conv)}
- moreover {assume b: "b < 0"
- {assume b': "?b' \<ge> 0"
+ by (simp add: isnormNum_def normNum_def Let_def split_def)}
+ moreover {
+ assume b: "b < 0"
+ { assume b': "?b' \<ge> 0"
from gpos have th: "?g \<ge> 0" by arith
from mult_nonneg_nonneg[OF th b'] zdvd_mult_div_cancel[OF gdvd(2)]
have False using b by arith }
- hence b': "?b' < 0" by (presburger add: linorder_not_le[symmetric])
+ hence b': "?b' < 0" by (presburger add: linorder_not_le[symmetric])
from anz bnz nz' b b' gp1 have ?thesis
- by (simp add: isnormNum_def normNum_def Let_def split_def)}
+ by (simp add: isnormNum_def normNum_def Let_def split_def) }
ultimately have ?thesis by blast
}
ultimately show ?thesis by blast
@@ -75,50 +69,42 @@
text {* Arithmetic over Num *}
-definition
- Nadd :: "Num \<Rightarrow> Num \<Rightarrow> Num" (infixl "+\<^sub>N" 60)
-where
- "Nadd = (\<lambda>(a,b) (a',b'). if a = 0 \<or> b = 0 then normNum(a',b')
+definition Nadd :: "Num \<Rightarrow> Num \<Rightarrow> Num" (infixl "+\<^sub>N" 60) where
+ "Nadd = (\<lambda>(a,b) (a',b'). if a = 0 \<or> b = 0 then normNum(a',b')
else if a'=0 \<or> b' = 0 then normNum(a,b)
else normNum(a*b' + b*a', b*b'))"
-definition
- Nmul :: "Num \<Rightarrow> Num \<Rightarrow> Num" (infixl "*\<^sub>N" 60)
-where
+definition Nmul :: "Num \<Rightarrow> Num \<Rightarrow> Num" (infixl "*\<^sub>N" 60) where
"Nmul = (\<lambda>(a,b) (a',b'). let g = gcd (a*a') (b*b')
in (a*a' div g, b*b' div g))"
-definition
- Nneg :: "Num \<Rightarrow> Num" ("~\<^sub>N")
-where
- "Nneg \<equiv> (\<lambda>(a,b). (-a,b))"
+definition Nneg :: "Num \<Rightarrow> Num" ("~\<^sub>N")
+ where "Nneg \<equiv> (\<lambda>(a,b). (-a,b))"
-definition
- Nsub :: "Num \<Rightarrow> Num \<Rightarrow> Num" (infixl "-\<^sub>N" 60)
-where
- "Nsub = (\<lambda>a b. a +\<^sub>N ~\<^sub>N b)"
+definition Nsub :: "Num \<Rightarrow> Num \<Rightarrow> Num" (infixl "-\<^sub>N" 60)
+ where "Nsub = (\<lambda>a b. a +\<^sub>N ~\<^sub>N b)"
-definition
- Ninv :: "Num \<Rightarrow> Num"
-where
- "Ninv \<equiv> \<lambda>(a,b). if a < 0 then (-b, \<bar>a\<bar>) else (b,a)"
+definition Ninv :: "Num \<Rightarrow> Num"
+ where "Ninv = (\<lambda>(a,b). if a < 0 then (-b, \<bar>a\<bar>) else (b,a))"
-definition
- Ndiv :: "Num \<Rightarrow> Num \<Rightarrow> Num" (infixl "\<div>\<^sub>N" 60)
-where
- "Ndiv \<equiv> \<lambda>a b. a *\<^sub>N Ninv b"
+definition Ndiv :: "Num \<Rightarrow> Num \<Rightarrow> Num" (infixl "\<div>\<^sub>N" 60)
+ where "Ndiv = (\<lambda>a b. a *\<^sub>N Ninv b)"
lemma Nneg_normN[simp]: "isnormNum x \<Longrightarrow> isnormNum (~\<^sub>N x)"
- by(simp add: isnormNum_def Nneg_def split_def)
+ by (simp add: isnormNum_def Nneg_def split_def)
+
lemma Nadd_normN[simp]: "isnormNum (x +\<^sub>N y)"
by (simp add: Nadd_def split_def)
+
lemma Nsub_normN[simp]: "\<lbrakk> isnormNum y\<rbrakk> \<Longrightarrow> isnormNum (x -\<^sub>N y)"
by (simp add: Nsub_def split_def)
-lemma Nmul_normN[simp]: assumes xn:"isnormNum x" and yn: "isnormNum y"
+
+lemma Nmul_normN[simp]:
+ assumes xn:"isnormNum x" and yn: "isnormNum y"
shows "isnormNum (x *\<^sub>N y)"
-proof-
+proof -
have "\<exists>a b. x = (a,b)" and "\<exists> a' b'. y = (a',b')" by auto
- then obtain a b a' b' where ab: "x = (a,b)" and ab': "y = (a',b')" by blast
+ then obtain a b a' b' where ab: "x = (a,b)" and ab': "y = (a',b')" by blast
{assume "a = 0"
hence ?thesis using xn ab ab'
by (simp add: isnormNum_def Let_def Nmul_def split_def)}
@@ -146,38 +132,25 @@
text {* Relations over Num *}
-definition
- Nlt0:: "Num \<Rightarrow> bool" ("0>\<^sub>N")
-where
- "Nlt0 = (\<lambda>(a,b). a < 0)"
+definition Nlt0:: "Num \<Rightarrow> bool" ("0>\<^sub>N")
+ where "Nlt0 = (\<lambda>(a,b). a < 0)"
-definition
- Nle0:: "Num \<Rightarrow> bool" ("0\<ge>\<^sub>N")
-where
- "Nle0 = (\<lambda>(a,b). a \<le> 0)"
+definition Nle0:: "Num \<Rightarrow> bool" ("0\<ge>\<^sub>N")
+ where "Nle0 = (\<lambda>(a,b). a \<le> 0)"
-definition
- Ngt0:: "Num \<Rightarrow> bool" ("0<\<^sub>N")
-where
- "Ngt0 = (\<lambda>(a,b). a > 0)"
+definition Ngt0:: "Num \<Rightarrow> bool" ("0<\<^sub>N")
+ where "Ngt0 = (\<lambda>(a,b). a > 0)"
-definition
- Nge0:: "Num \<Rightarrow> bool" ("0\<le>\<^sub>N")
-where
- "Nge0 = (\<lambda>(a,b). a \<ge> 0)"
+definition Nge0:: "Num \<Rightarrow> bool" ("0\<le>\<^sub>N")
+ where "Nge0 = (\<lambda>(a,b). a \<ge> 0)"
-definition
- Nlt :: "Num \<Rightarrow> Num \<Rightarrow> bool" (infix "<\<^sub>N" 55)
-where
- "Nlt = (\<lambda>a b. 0>\<^sub>N (a -\<^sub>N b))"
+definition Nlt :: "Num \<Rightarrow> Num \<Rightarrow> bool" (infix "<\<^sub>N" 55)
+ where "Nlt = (\<lambda>a b. 0>\<^sub>N (a -\<^sub>N b))"
-definition
- Nle :: "Num \<Rightarrow> Num \<Rightarrow> bool" (infix "\<le>\<^sub>N" 55)
-where
- "Nle = (\<lambda>a b. 0\<ge>\<^sub>N (a -\<^sub>N b))"
+definition Nle :: "Num \<Rightarrow> Num \<Rightarrow> bool" (infix "\<le>\<^sub>N" 55)
+ where "Nle = (\<lambda>a b. 0\<ge>\<^sub>N (a -\<^sub>N b))"
-definition
- "INum = (\<lambda>(a,b). of_int a / of_int b)"
+definition "INum = (\<lambda>(a,b). of_int a / of_int b)"
lemma INum_int [simp]: "INum (i\<^sub>N) = ((of_int i) ::'a::field)" "INum 0\<^sub>N = (0::'a::field)"
by (simp_all add: INum_def)
@@ -189,9 +162,9 @@
have "\<exists> a b a' b'. x = (a,b) \<and> y = (a',b')" by auto
then obtain a b a' b' where xy[simp]: "x = (a,b)" "y=(a',b')" by blast
assume H: ?lhs
- {assume "a = 0 \<or> b = 0 \<or> a' = 0 \<or> b' = 0"
+ { assume "a = 0 \<or> b = 0 \<or> a' = 0 \<or> b' = 0"
hence ?rhs using na nb H
- by (simp add: INum_def split_def isnormNum_def split: split_if_asm)}
+ by (simp add: INum_def split_def isnormNum_def split: split_if_asm) }
moreover
{ assume az: "a \<noteq> 0" and bz: "b \<noteq> 0" and a'z: "a'\<noteq>0" and b'z: "b'\<noteq>0"
from az bz a'z b'z na nb have pos: "b > 0" "b' > 0" by (simp_all add: isnormNum_def)
@@ -217,9 +190,10 @@
qed
-lemma isnormNum0[simp]: "isnormNum x \<Longrightarrow> (INum x = (0::'a::{field_char_0, field_inverse_zero})) = (x = 0\<^sub>N)"
+lemma isnormNum0[simp]:
+ "isnormNum x \<Longrightarrow> (INum x = (0::'a::{field_char_0, field_inverse_zero})) = (x = 0\<^sub>N)"
unfolding INum_int(2)[symmetric]
- by (rule isnormNum_unique, simp_all)
+ by (rule isnormNum_unique) simp_all
lemma of_int_div_aux: "d ~= 0 ==> ((of_int x)::'a::field_char_0) / (of_int d) =
of_int (x div d) + (of_int (x mod d)) / ((of_int d)::'a)"
@@ -241,25 +215,27 @@
apply (frule of_int_div_aux [of d n, where ?'a = 'a])
apply simp
apply (simp add: dvd_eq_mod_eq_0)
-done
+ done
lemma normNum[simp]: "INum (normNum x) = (INum x :: 'a::{field_char_0, field_inverse_zero})"
-proof-
+proof -
have "\<exists> a b. x = (a,b)" by auto
- then obtain a b where x[simp]: "x = (a,b)" by blast
- {assume "a=0 \<or> b = 0" hence ?thesis
- by (simp add: INum_def normNum_def split_def Let_def)}
+ then obtain a b where x: "x = (a,b)" by blast
+ { assume "a=0 \<or> b = 0" hence ?thesis
+ by (simp add: x INum_def normNum_def split_def Let_def)}
moreover
- {assume a: "a\<noteq>0" and b: "b\<noteq>0"
+ { assume a: "a\<noteq>0" and b: "b\<noteq>0"
let ?g = "gcd a b"
from a b have g: "?g \<noteq> 0"by simp
from of_int_div[OF g, where ?'a = 'a]
- have ?thesis by (auto simp add: INum_def normNum_def split_def Let_def)}
+ have ?thesis by (auto simp add: x INum_def normNum_def split_def Let_def) }
ultimately show ?thesis by blast
qed
-lemma INum_normNum_iff: "(INum x ::'a::{field_char_0, field_inverse_zero}) = INum y \<longleftrightarrow> normNum x = normNum y" (is "?lhs = ?rhs")
+lemma INum_normNum_iff:
+ "(INum x ::'a::{field_char_0, field_inverse_zero}) = INum y \<longleftrightarrow> normNum x = normNum y"
+ (is "?lhs = ?rhs")
proof -
have "normNum x = normNum y \<longleftrightarrow> (INum (normNum x) :: 'a) = INum (normNum y)"
by (simp del: normNum)
@@ -268,139 +244,159 @@
qed
lemma Nadd[simp]: "INum (x +\<^sub>N y) = INum x + (INum y :: 'a :: {field_char_0, field_inverse_zero})"
-proof-
-let ?z = "0:: 'a"
- have " \<exists> a b. x = (a,b)" " \<exists> a' b'. y = (a',b')" by auto
- then obtain a b a' b' where x[simp]: "x = (a,b)"
+proof -
+ let ?z = "0:: 'a"
+ have "\<exists>a b. x = (a,b)" " \<exists> a' b'. y = (a',b')" by auto
+ then obtain a b a' b' where x: "x = (a,b)"
and y[simp]: "y = (a',b')" by blast
- {assume "a=0 \<or> a'= 0 \<or> b =0 \<or> b' = 0" hence ?thesis
- apply (cases "a=0",simp_all add: Nadd_def)
- apply (cases "b= 0",simp_all add: INum_def)
- apply (cases "a'= 0",simp_all)
- apply (cases "b'= 0",simp_all)
+ { assume "a=0 \<or> a'= 0 \<or> b =0 \<or> b' = 0"
+ hence ?thesis
+ apply (cases "a=0", simp_all add: x Nadd_def)
+ apply (cases "b= 0", simp_all add: INum_def)
+ apply (cases "a'= 0", simp_all)
+ apply (cases "b'= 0", simp_all)
done }
moreover
- {assume aa':"a \<noteq> 0" "a'\<noteq> 0" and bb': "b \<noteq> 0" "b' \<noteq> 0"
- {assume z: "a * b' + b * a' = 0"
+ { assume aa':"a \<noteq> 0" "a'\<noteq> 0" and bb': "b \<noteq> 0" "b' \<noteq> 0"
+ { assume z: "a * b' + b * a' = 0"
hence "of_int (a*b' + b*a') / (of_int b* of_int b') = ?z" by simp
- hence "of_int b' * of_int a / (of_int b * of_int b') + of_int b * of_int a' / (of_int b * of_int b') = ?z" by (simp add:add_divide_distrib)
- hence th: "of_int a / of_int b + of_int a' / of_int b' = ?z" using bb' aa' by simp
+ hence "of_int b' * of_int a / (of_int b * of_int b') + of_int b * of_int a' / (of_int b * of_int b') = ?z"
+ by (simp add:add_divide_distrib)
+ hence th: "of_int a / of_int b + of_int a' / of_int b' = ?z" using bb' aa'
+ by simp
from z aa' bb' have ?thesis
- by (simp add: th Nadd_def normNum_def INum_def split_def)}
- moreover {assume z: "a * b' + b * a' \<noteq> 0"
+ by (simp add: x th Nadd_def normNum_def INum_def split_def) }
+ moreover {
+ assume z: "a * b' + b * a' \<noteq> 0"
let ?g = "gcd (a * b' + b * a') (b*b')"
have gz: "?g \<noteq> 0" using z by simp
have ?thesis using aa' bb' z gz
- of_int_div[where ?'a = 'a, OF gz gcd_dvd1_int[where x="a * b' + b * a'" and y="b*b'"]] of_int_div[where ?'a = 'a,
- OF gz gcd_dvd2_int[where x="a * b' + b * a'" and y="b*b'"]]
- by (simp add: Nadd_def INum_def normNum_def Let_def add_divide_distrib)}
- ultimately have ?thesis using aa' bb'
- by (simp add: Nadd_def INum_def normNum_def Let_def) }
+ of_int_div[where ?'a = 'a, OF gz gcd_dvd1_int[where x="a * b' + b * a'" and y="b*b'"]]
+ of_int_div[where ?'a = 'a, OF gz gcd_dvd2_int[where x="a * b' + b * a'" and y="b*b'"]]
+ by (simp add: x Nadd_def INum_def normNum_def Let_def add_divide_distrib)}
+ ultimately have ?thesis using aa' bb'
+ by (simp add: x Nadd_def INum_def normNum_def Let_def) }
ultimately show ?thesis by blast
qed
-lemma Nmul[simp]: "INum (x *\<^sub>N y) = INum x * (INum y:: 'a :: {field_char_0, field_inverse_zero}) "
-proof-
+lemma Nmul[simp]: "INum (x *\<^sub>N y) = INum x * (INum y:: 'a :: {field_char_0, field_inverse_zero})"
+proof -
let ?z = "0::'a"
- have " \<exists> a b. x = (a,b)" " \<exists> a' b'. y = (a',b')" by auto
+ have "\<exists>a b. x = (a,b)" " \<exists> a' b'. y = (a',b')" by auto
then obtain a b a' b' where x: "x = (a,b)" and y: "y = (a',b')" by blast
- {assume "a=0 \<or> a'= 0 \<or> b = 0 \<or> b' = 0" hence ?thesis
- apply (cases "a=0",simp_all add: x y Nmul_def INum_def Let_def)
- apply (cases "b=0",simp_all)
- apply (cases "a'=0",simp_all)
+ { assume "a=0 \<or> a'= 0 \<or> b = 0 \<or> b' = 0"
+ hence ?thesis
+ apply (cases "a=0", simp_all add: x y Nmul_def INum_def Let_def)
+ apply (cases "b=0", simp_all)
+ apply (cases "a'=0", simp_all)
done }
moreover
- {assume z: "a \<noteq> 0" "a' \<noteq> 0" "b \<noteq> 0" "b' \<noteq> 0"
+ { assume z: "a \<noteq> 0" "a' \<noteq> 0" "b \<noteq> 0" "b' \<noteq> 0"
let ?g="gcd (a*a') (b*b')"
have gz: "?g \<noteq> 0" using z by simp
- from z of_int_div[where ?'a = 'a, OF gz gcd_dvd1_int[where x="a*a'" and y="b*b'"]]
+ from z of_int_div[where ?'a = 'a, OF gz gcd_dvd1_int[where x="a*a'" and y="b*b'"]]
of_int_div[where ?'a = 'a , OF gz gcd_dvd2_int[where x="a*a'" and y="b*b'"]]
- have ?thesis by (simp add: Nmul_def x y Let_def INum_def)}
+ have ?thesis by (simp add: Nmul_def x y Let_def INum_def) }
ultimately show ?thesis by blast
qed
lemma Nneg[simp]: "INum (~\<^sub>N x) = - (INum x ::'a:: field)"
by (simp add: Nneg_def split_def INum_def)
-lemma Nsub[simp]: shows "INum (x -\<^sub>N y) = INum x - (INum y:: 'a :: {field_char_0, field_inverse_zero})"
-by (simp add: Nsub_def split_def)
+lemma Nsub[simp]: "INum (x -\<^sub>N y) = INum x - (INum y:: 'a :: {field_char_0, field_inverse_zero})"
+ by (simp add: Nsub_def split_def)
lemma Ninv[simp]: "INum (Ninv x) = (1::'a :: field_inverse_zero) / (INum x)"
by (simp add: Ninv_def INum_def split_def)
-lemma Ndiv[simp]: "INum (x \<div>\<^sub>N y) = INum x / (INum y ::'a :: {field_char_0, field_inverse_zero})" by (simp add: Ndiv_def)
+lemma Ndiv[simp]: "INum (x \<div>\<^sub>N y) = INum x / (INum y ::'a :: {field_char_0, field_inverse_zero})"
+ by (simp add: Ndiv_def)
-lemma Nlt0_iff[simp]: assumes nx: "isnormNum x"
- shows "((INum x :: 'a :: {field_char_0, linordered_field_inverse_zero})< 0) = 0>\<^sub>N x "
-proof-
- have " \<exists> a b. x = (a,b)" by simp
+lemma Nlt0_iff[simp]:
+ assumes nx: "isnormNum x"
+ shows "((INum x :: 'a :: {field_char_0, linordered_field_inverse_zero})< 0) = 0>\<^sub>N x"
+proof -
+ have "\<exists> a b. x = (a,b)" by simp
then obtain a b where x[simp]:"x = (a,b)" by blast
{assume "a = 0" hence ?thesis by (simp add: Nlt0_def INum_def) }
moreover
- {assume a: "a\<noteq>0" hence b: "(of_int b::'a) > 0" using nx by (simp add: isnormNum_def)
+ { assume a: "a\<noteq>0" hence b: "(of_int b::'a) > 0" using nx by (simp add: isnormNum_def)
from pos_divide_less_eq[OF b, where b="of_int a" and a="0::'a"]
- have ?thesis by (simp add: Nlt0_def INum_def)}
+ have ?thesis by (simp add: Nlt0_def INum_def) }
ultimately show ?thesis by blast
qed
-lemma Nle0_iff[simp]:assumes nx: "isnormNum x"
+lemma Nle0_iff[simp]:
+ assumes nx: "isnormNum x"
shows "((INum x :: 'a :: {field_char_0, linordered_field_inverse_zero}) \<le> 0) = 0\<ge>\<^sub>N x"
-proof-
- have " \<exists> a b. x = (a,b)" by simp
+proof -
+ have "\<exists>a b. x = (a,b)" by simp
then obtain a b where x[simp]:"x = (a,b)" by blast
- {assume "a = 0" hence ?thesis by (simp add: Nle0_def INum_def) }
+ { assume "a = 0" hence ?thesis by (simp add: Nle0_def INum_def) }
moreover
- {assume a: "a\<noteq>0" hence b: "(of_int b :: 'a) > 0" using nx by (simp add: isnormNum_def)
+ { assume a: "a\<noteq>0" hence b: "(of_int b :: 'a) > 0" using nx by (simp add: isnormNum_def)
from pos_divide_le_eq[OF b, where b="of_int a" and a="0::'a"]
have ?thesis by (simp add: Nle0_def INum_def)}
ultimately show ?thesis by blast
qed
-lemma Ngt0_iff[simp]:assumes nx: "isnormNum x" shows "((INum x :: 'a :: {field_char_0, linordered_field_inverse_zero})> 0) = 0<\<^sub>N x"
-proof-
- have " \<exists> a b. x = (a,b)" by simp
+lemma Ngt0_iff[simp]:
+ assumes nx: "isnormNum x"
+ shows "((INum x :: 'a :: {field_char_0, linordered_field_inverse_zero})> 0) = 0<\<^sub>N x"
+proof -
+ have "\<exists> a b. x = (a,b)" by simp
then obtain a b where x[simp]:"x = (a,b)" by blast
- {assume "a = 0" hence ?thesis by (simp add: Ngt0_def INum_def) }
+ { assume "a = 0" hence ?thesis by (simp add: Ngt0_def INum_def) }
moreover
- {assume a: "a\<noteq>0" hence b: "(of_int b::'a) > 0" using nx by (simp add: isnormNum_def)
+ { assume a: "a\<noteq>0" hence b: "(of_int b::'a) > 0" using nx
+ by (simp add: isnormNum_def)
from pos_less_divide_eq[OF b, where b="of_int a" and a="0::'a"]
- have ?thesis by (simp add: Ngt0_def INum_def)}
- ultimately show ?thesis by blast
-qed
-lemma Nge0_iff[simp]:assumes nx: "isnormNum x"
- shows "((INum x :: 'a :: {field_char_0, linordered_field_inverse_zero}) \<ge> 0) = 0\<le>\<^sub>N x"
-proof-
- have " \<exists> a b. x = (a,b)" by simp
- then obtain a b where x[simp]:"x = (a,b)" by blast
- {assume "a = 0" hence ?thesis by (simp add: Nge0_def INum_def) }
- moreover
- {assume a: "a\<noteq>0" hence b: "(of_int b::'a) > 0" using nx by (simp add: isnormNum_def)
- from pos_le_divide_eq[OF b, where b="of_int a" and a="0::'a"]
- have ?thesis by (simp add: Nge0_def INum_def)}
+ have ?thesis by (simp add: Ngt0_def INum_def) }
ultimately show ?thesis by blast
qed
-lemma Nlt_iff[simp]: assumes nx: "isnormNum x" and ny: "isnormNum y"
+lemma Nge0_iff[simp]:
+ assumes nx: "isnormNum x"
+ shows "((INum x :: 'a :: {field_char_0, linordered_field_inverse_zero}) \<ge> 0) = 0\<le>\<^sub>N x"
+proof -
+ have "\<exists> a b. x = (a,b)" by simp
+ then obtain a b where x[simp]:"x = (a,b)" by blast
+ { assume "a = 0" hence ?thesis by (simp add: Nge0_def INum_def) }
+ moreover
+ { assume "a \<noteq> 0" hence b: "(of_int b::'a) > 0" using nx
+ by (simp add: isnormNum_def)
+ from pos_le_divide_eq[OF b, where b="of_int a" and a="0::'a"]
+ have ?thesis by (simp add: Nge0_def INum_def) }
+ ultimately show ?thesis by blast
+qed
+
+lemma Nlt_iff[simp]:
+ assumes nx: "isnormNum x" and ny: "isnormNum y"
shows "((INum x :: 'a :: {field_char_0, linordered_field_inverse_zero}) < INum y) = (x <\<^sub>N y)"
-proof-
+proof -
let ?z = "0::'a"
- have "((INum x ::'a) < INum y) = (INum (x -\<^sub>N y) < ?z)" using nx ny by simp
- also have "\<dots> = (0>\<^sub>N (x -\<^sub>N y))" using Nlt0_iff[OF Nsub_normN[OF ny]] by simp
+ have "((INum x ::'a) < INum y) = (INum (x -\<^sub>N y) < ?z)"
+ using nx ny by simp
+ also have "\<dots> = (0>\<^sub>N (x -\<^sub>N y))"
+ using Nlt0_iff[OF Nsub_normN[OF ny]] by simp
finally show ?thesis by (simp add: Nlt_def)
qed
-lemma Nle_iff[simp]: assumes nx: "isnormNum x" and ny: "isnormNum y"
+lemma Nle_iff[simp]:
+ assumes nx: "isnormNum x" and ny: "isnormNum y"
shows "((INum x :: 'a :: {field_char_0, linordered_field_inverse_zero})\<le> INum y) = (x \<le>\<^sub>N y)"
-proof-
- have "((INum x ::'a) \<le> INum y) = (INum (x -\<^sub>N y) \<le> (0::'a))" using nx ny by simp
- also have "\<dots> = (0\<ge>\<^sub>N (x -\<^sub>N y))" using Nle0_iff[OF Nsub_normN[OF ny]] by simp
+proof -
+ have "((INum x ::'a) \<le> INum y) = (INum (x -\<^sub>N y) \<le> (0::'a))"
+ using nx ny by simp
+ also have "\<dots> = (0\<ge>\<^sub>N (x -\<^sub>N y))"
+ using Nle0_iff[OF Nsub_normN[OF ny]] by simp
finally show ?thesis by (simp add: Nle_def)
qed
lemma Nadd_commute:
assumes "SORT_CONSTRAINT('a::{field_char_0, field_inverse_zero})"
shows "x +\<^sub>N y = y +\<^sub>N x"
-proof-
+proof -
have n: "isnormNum (x +\<^sub>N y)" "isnormNum (y +\<^sub>N x)" by simp_all
have "(INum (x +\<^sub>N y)::'a) = INum (y +\<^sub>N x)" by simp
with isnormNum_unique[OF n] show ?thesis by simp
@@ -422,12 +418,11 @@
assumes "SORT_CONSTRAINT('a::{field_char_0, field_inverse_zero})"
assumes nx: "isnormNum x"
shows "normNum x = x"
-proof-
+proof -
let ?a = "normNum x"
have n: "isnormNum ?a" by simp
- have th:"INum ?a = (INum x ::'a)" by simp
- with isnormNum_unique[OF n nx]
- show ?thesis by simp
+ have th: "INum ?a = (INum x ::'a)" by simp
+ with isnormNum_unique[OF n nx] show ?thesis by simp
qed
lemma normNum_nilpotent[simp]:
@@ -445,7 +440,7 @@
lemma Nadd_normNum1[simp]:
assumes "SORT_CONSTRAINT('a::{field_char_0, field_inverse_zero})"
shows "normNum x +\<^sub>N y = x +\<^sub>N y"
-proof-
+proof -
have n: "isnormNum (normNum x +\<^sub>N y)" "isnormNum (x +\<^sub>N y)" by simp_all
have "INum (normNum x +\<^sub>N y) = INum x + (INum y :: 'a)" by simp
also have "\<dots> = INum (x +\<^sub>N y)" by simp
@@ -455,7 +450,7 @@
lemma Nadd_normNum2[simp]:
assumes "SORT_CONSTRAINT('a::{field_char_0, field_inverse_zero})"
shows "x +\<^sub>N normNum y = x +\<^sub>N y"
-proof-
+proof -
have n: "isnormNum (x +\<^sub>N normNum y)" "isnormNum (x +\<^sub>N y)" by simp_all
have "INum (x +\<^sub>N normNum y) = INum x + (INum y :: 'a)" by simp
also have "\<dots> = INum (x +\<^sub>N y)" by simp
@@ -465,7 +460,7 @@
lemma Nadd_assoc:
assumes "SORT_CONSTRAINT('a::{field_char_0, field_inverse_zero})"
shows "x +\<^sub>N y +\<^sub>N z = x +\<^sub>N (y +\<^sub>N z)"
-proof-
+proof -
have n: "isnormNum (x +\<^sub>N y +\<^sub>N z)" "isnormNum (x +\<^sub>N (y +\<^sub>N z))" by simp_all
have "INum (x +\<^sub>N y +\<^sub>N z) = (INum (x +\<^sub>N (y +\<^sub>N z)) :: 'a)" by simp
with isnormNum_unique[OF n] show ?thesis by simp
@@ -478,7 +473,7 @@
assumes "SORT_CONSTRAINT('a::{field_char_0, field_inverse_zero})"
assumes nx: "isnormNum x" and ny:"isnormNum y" and nz:"isnormNum z"
shows "x *\<^sub>N y *\<^sub>N z = x *\<^sub>N (y *\<^sub>N z)"
-proof-
+proof -
from nx ny nz have n: "isnormNum (x *\<^sub>N y *\<^sub>N z)" "isnormNum (x *\<^sub>N (y *\<^sub>N z))"
by simp_all
have "INum (x +\<^sub>N y +\<^sub>N z) = (INum (x +\<^sub>N (y +\<^sub>N z)) :: 'a)" by simp
@@ -488,13 +483,13 @@
lemma Nsub0:
assumes "SORT_CONSTRAINT('a::{field_char_0, field_inverse_zero})"
assumes x: "isnormNum x" and y:"isnormNum y" shows "(x -\<^sub>N y = 0\<^sub>N) = (x = y)"
-proof-
- { fix h :: 'a
- from isnormNum_unique[where 'a = 'a, OF Nsub_normN[OF y], where y="0\<^sub>N"]
- have "(x -\<^sub>N y = 0\<^sub>N) = (INum (x -\<^sub>N y) = (INum 0\<^sub>N :: 'a)) " by simp
- also have "\<dots> = (INum x = (INum y :: 'a))" by simp
- also have "\<dots> = (x = y)" using x y by simp
- finally show ?thesis . }
+proof -
+ fix h :: 'a
+ from isnormNum_unique[where 'a = 'a, OF Nsub_normN[OF y], where y="0\<^sub>N"]
+ have "(x -\<^sub>N y = 0\<^sub>N) = (INum (x -\<^sub>N y) = (INum 0\<^sub>N :: 'a)) " by simp
+ also have "\<dots> = (INum x = (INum y :: 'a))" by simp
+ also have "\<dots> = (x = y)" using x y by simp
+ finally show ?thesis .
qed
lemma Nmul0[simp]: "c *\<^sub>N 0\<^sub>N = 0\<^sub>N" " 0\<^sub>N *\<^sub>N c = 0\<^sub>N"
@@ -504,16 +499,18 @@
assumes "SORT_CONSTRAINT('a::{field_char_0, field_inverse_zero})"
assumes nx:"isnormNum x" and ny: "isnormNum y"
shows "(x*\<^sub>N y = 0\<^sub>N) = (x = 0\<^sub>N \<or> y = 0\<^sub>N)"
-proof-
- { fix h :: 'a
- have " \<exists> a b a' b'. x = (a,b) \<and> y= (a',b')" by auto
- then obtain a b a' b' where xy[simp]: "x = (a,b)" "y = (a',b')" by blast
- have n0: "isnormNum 0\<^sub>N" by simp
- show ?thesis using nx ny
- apply (simp only: isnormNum_unique[where ?'a = 'a, OF Nmul_normN[OF nx ny] n0, symmetric] Nmul[where ?'a = 'a])
- by (simp add: INum_def split_def isnormNum_def split: split_if_asm)
- }
+proof -
+ fix h :: 'a
+ have " \<exists> a b a' b'. x = (a,b) \<and> y= (a',b')" by auto
+ then obtain a b a' b' where xy[simp]: "x = (a,b)" "y = (a',b')" by blast
+ have n0: "isnormNum 0\<^sub>N" by simp
+ show ?thesis using nx ny
+ apply (simp only: isnormNum_unique[where ?'a = 'a, OF Nmul_normN[OF nx ny] n0, symmetric]
+ Nmul[where ?'a = 'a])
+ apply (simp add: INum_def split_def isnormNum_def split: split_if_asm)
+ done
qed
+
lemma Nneg_Nneg[simp]: "~\<^sub>N (~\<^sub>N c) = c"
by (simp add: Nneg_def split_def)