Ask Your Question

How do I define a homomorphism of a graded commutative algebra?

asked 2018-04-28 19:14:46 +0200

ronno gravatar image

updated 2023-01-09 23:59:46 +0200

tmonteil gravatar image

Why does the following throw a TypeError: images do not define a valid homomorphism?

E = GradedCommutativeAlgebra(QQ,'x,y',degrees=(1,1))
f = E.hom([x,y])

I expected it to define $f$ to be the identity homomorphism of $E$. What is the right way to define a homomorphism of $E$? I'm more interested in the one that switches $x$ and $y$ than the identity homomorphism, but this seemed a more obvious version of the question.

edit retag flag offensive close merge delete


I am working on implementing morphisms of graded commutative algebras. No promises about when it might be done, but what are you interested in doing with the morphisms? What features would you like to have?

John Palmieri gravatar imageJohn Palmieri ( 2018-08-27 20:51:55 +0200 )edit

@JohnPalmieri Extremely late response but I want to be able to compute the trace of an endomorphism of a cdga on the cohomology, (multi)degree by (multi)degree, assuming degreewise finite dimensionality.

ronno gravatar imageronno ( 2023-09-25 10:28:05 +0200 )edit

1 Answer

Sort by ยป oldest newest most voted

answered 2018-05-01 19:21:26 +0200

updated 2018-05-03 00:35:23 +0200

slelievre gravatar image

This looks like a bug, and I'm not sure of a workaround yet. I created a ticket for it here.

edit flag offensive delete link more

Your Answer

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

Add Answer

Question Tools

1 follower


Asked: 2018-04-28 19:14:46 +0200

Seen: 406 times

Last updated: May 03 '18