# HG changeset patch # User huffman # Date 1273013082 25200 # Node ID 5d37a96de20c6eff0553ecfcfd8eea131ab2ee01 # Parent f75b13ed4898f74539ea12a89d01489bb4c268cc generalize more lemmas about limits diff -r f75b13ed4898 -r 5d37a96de20c src/HOL/Lim.thy --- a/src/HOL/Lim.thy Tue May 04 13:11:15 2010 -0700 +++ b/src/HOL/Lim.thy Tue May 04 15:44:42 2010 -0700 @@ -381,7 +381,7 @@ lemmas LIM_of_real = of_real.LIM lemma LIM_power: - fixes f :: "'a::metric_space \ 'b::{power,real_normed_algebra}" + fixes f :: "'a::topological_space \ 'b::{power,real_normed_algebra}" assumes f: "f -- a --> l" shows "(\x. f x ^ n) -- a --> l ^ n" by (induct n, simp, simp add: LIM_mult f) @@ -399,7 +399,7 @@ by (rule LIM_inverse [OF LIM_ident a]) lemma LIM_sgn: - fixes f :: "'a::metric_space \ 'b::real_normed_vector" + fixes f :: "'a::topological_space \ 'b::real_normed_vector" shows "\f -- a --> l; l \ 0\ \ (\x. sgn (f x)) -- a --> sgn l" unfolding sgn_div_norm by (simp add: LIM_scaleR LIM_inverse LIM_norm) @@ -408,12 +408,12 @@ subsection {* Continuity *} lemma LIM_isCont_iff: - fixes f :: "'a::real_normed_vector \ 'b::metric_space" + fixes f :: "'a::real_normed_vector \ 'b::topological_space" shows "(f -- a --> f a) = ((\h. f (a + h)) -- 0 --> f a)" by (rule iffI [OF LIM_offset_zero LIM_offset_zero_cancel]) lemma isCont_iff: - fixes f :: "'a::real_normed_vector \ 'b::metric_space" + fixes f :: "'a::real_normed_vector \ 'b::topological_space" shows "isCont f x = (\h. f (x + h)) -- 0 --> f x" by (simp add: isCont_def LIM_isCont_iff) @@ -424,7 +424,7 @@ unfolding isCont_def by (rule LIM_const) lemma isCont_norm: - fixes f :: "'a::metric_space \ 'b::real_normed_vector" + fixes f :: "'a::topological_space \ 'b::real_normed_vector" shows "isCont f a \ isCont (\x. norm (f x)) a" unfolding isCont_def by (rule LIM_norm) @@ -432,27 +432,27 @@ unfolding isCont_def by (rule LIM_rabs) lemma isCont_add: - fixes f :: "'a::metric_space \ 'b::real_normed_vector" + fixes f :: "'a::topological_space \ 'b::real_normed_vector" shows "\isCont f a; isCont g a\ \ isCont (\x. f x + g x) a" unfolding isCont_def by (rule LIM_add) lemma isCont_minus: - fixes f :: "'a::metric_space \ 'b::real_normed_vector" + fixes f :: "'a::topological_space \ 'b::real_normed_vector" shows "isCont f a \ isCont (\x. - f x) a" unfolding isCont_def by (rule LIM_minus) lemma isCont_diff: - fixes f :: "'a::metric_space \ 'b::real_normed_vector" + fixes f :: "'a::topological_space \ 'b::real_normed_vector" shows "\isCont f a; isCont g a\ \ isCont (\x. f x - g x) a" unfolding isCont_def by (rule LIM_diff) lemma isCont_mult: - fixes f g :: "'a::metric_space \ 'b::real_normed_algebra" + fixes f g :: "'a::topological_space \ 'b::real_normed_algebra" shows "\isCont f a; isCont g a\ \ isCont (\x. f x * g x) a" unfolding isCont_def by (rule LIM_mult) lemma isCont_inverse: - fixes f :: "'a::metric_space \ 'b::real_normed_div_algebra" + fixes f :: "'a::topological_space \ 'b::real_normed_div_algebra" shows "\isCont f a; f a \ 0\ \ isCont (\x. inverse (f x)) a" unfolding isCont_def by (rule LIM_inverse) @@ -495,12 +495,12 @@ unfolding isCont_def by (rule LIM_of_real) lemma isCont_power: - fixes f :: "'a::metric_space \ 'b::{power,real_normed_algebra}" + fixes f :: "'a::topological_space \ 'b::{power,real_normed_algebra}" shows "isCont f a \ isCont (\x. f x ^ n) a" unfolding isCont_def by (rule LIM_power) lemma isCont_sgn: - fixes f :: "'a::metric_space \ 'b::real_normed_vector" + fixes f :: "'a::topological_space \ 'b::real_normed_vector" shows "\isCont f a; f a \ 0\ \ isCont (\x. sgn (f x)) a" unfolding isCont_def by (rule LIM_sgn) @@ -508,7 +508,7 @@ by (rule isCont_rabs [OF isCont_ident]) lemma isCont_setsum: - fixes f :: "'a \ 'b::metric_space \ 'c::real_normed_vector" + fixes f :: "'a \ 'b::topological_space \ 'c::real_normed_vector" fixes A :: "'a set" assumes "finite A" shows "\ i \ A. isCont (f i) x \ isCont (\ x. \ i \ A. f i x) x" using `finite A`