Zulip Chat Archive
Stream: Is there code for X?
Topic: hasDerivWithinAt_pi for EuclideanSpace or Lp normed spaces
Michael Novak (Feb 22 2026 at 11:24):
Is there a theorem like docs#hasDerivWithinAt_pi for EuclideanSpace or normed Lp spaces? I can't find something exactly like this. Alternatively is there some other way of getting this?
Yury G. Kudryashov (Feb 22 2026 at 14:01):
You can add a pi version of docs#WithLp.prodContinuousLinearEquiv (probably, generalizing docs#EuclideanSpace.equiv), then combine the existing theorem with theorems about differentiabilty of ContinuousLinearEquivs.
Michael Novak (Feb 22 2026 at 16:46):
Yury G. Kudryashov said:
You can add a
piversion of docs#WithLp.prodContinuousLinearEquiv (probably, generalizing docs#EuclideanSpace.equiv), then combine the existing theorem with theorems about differentiabilty ofContinuousLinearEquivs.
Thank you very much!
Albert Smith (Feb 22 2026 at 16:54):
The equiv Yury suggests already exists, I believe, as docs#PiLp.continuousLinearEquiv
Yury G. Kudryashov (Feb 22 2026 at 17:33):
I forgot that loogle doesn't see through abbrevs.
Yury G. Kudryashov (Feb 22 2026 at 21:21):
:man_facepalming: See docs#differentiableWithinAt_piLp and other lemmas in that file.
Albert Smith (Feb 22 2026 at 21:36):
It seems there's also docs#hasFDerivWithinAt_euclidean for the special case of Euclidean space
Last updated: Feb 28 2026 at 14:05 UTC