witt index of quadratic form

asked 2017-01-01 21:09:29 +0200

user58293
25 ●2

An important invariant of quadratic forms $(V,q)$ over a field is the Witt index, the dimension of a maximal isotropic subspace of $V$.

Is Sage able to calculate this? I have checked http://doc.sagemath.org/html/en/refer... and there does not seem to be anything there to help me (but I may have overlooked it).

edit retag flag offensive close merge delete

add a comment

1 Answer

Sort by » oldest newest most voted

answered 2017-01-02 12:20:49 +0200

slelievre
17654 ●22 ●160 ●348 http://carva.org/samue...

updated 2017-01-05 16:24:44 +0200

Searching the Sage documentation and source seems to indicate there is nothing in Sage for that.

Indeed

sage: search_doc("witt")
sage: search_src("witt")

only have references to other Witt things.

However, there is a GAP package called "Forms" which you might find useful.

See

Forms in GAP package index: http://gap-system.org/Packages/forms.html
Forms package home page: http://cage.ugent.be/geometry/forms.php
Forms package documentation: http://cage.ugent.be/geometry/software/forms/chap0.html
"Witt index" entry: http://cage.ugent.be/geometry/software/forms/chap5.html#X85FA387280DAEA69

edit flag offensive delete link

add a comment

Your Answer

Please start posting anonymously - your entry will be published after you log in or create a new account.

Add Answer

Question Tools

Stats

Asked: 2017-01-01 21:09:29 +0200

Seen: 876 times

Last updated: Jan 05 '17

witt index of quadratic form edit

1 Answer