ASKSAGE: Sage Q&A Forum - RSS feedhttps://ask.sagemath.org/questions/Q&A Forum for SageenCopyright Sage, 2010. Some rights reserved under creative commons license.Wed, 19 Jun 2019 15:47:11 +0200How to make formal variables with more than one index?https://ask.sagemath.org/question/46942/how-to-make-formal-variables-with-more-than-one-index/I'd like to make formal variables that can be multiplied, added etc. but have them labelled by two indices.
Here:
https://ask.sagemath.org/question/7925/a-list-of-symbolic-variables/
it's done for variables with one index, and I asked a similar question about defining differential forms with multi-labels here:
https://ask.sagemath.org/question/46844/how-to-define-multiple-objects-with-a-for-loop/
I see no clear way of merging these two approaches. sum8tionWed, 19 Jun 2019 15:47:11 +0200https://ask.sagemath.org/question/46942/free algebra and indexed lettershttps://ask.sagemath.org/question/8601/free-algebra-and-indexed-letters/I try to work with a Combinatorial Free Module with basis a set of Words over an alphabet of indexed letters (y1,y2,...).
For example, I define
from sage.combinat.free_module import CombinatorialFreeModule as CFM
Mots=Words(['y1','y2','y3','y4','y5','y6','y7','y8'])
Module=CFM(QQ,Mots)
But I have some problems with the letters. For example :
mot=Word('y1')
sage: mot
word: y1
sage: mot in Mots
False
Is there a way to cure this problem ?Matthieu DeneufchâtelFri, 30 Dec 2011 12:41:57 +0100https://ask.sagemath.org/question/8601/