Matthias Zach

Results 41 issues of Matthias Zach

Two minor fixes to speed up the computation of cohomology. CC: @wdecker

I have to make a PR to see whether the tests are still running. They have become too big for my local machine. There is nothing to be reviewed here...

This is work in progress for all the small fixes necessary to make some old scripts of @simonbrandhorst and myself run again.

topic: rings
topic: schemes

CC: @wdecker , @jankoboehm

topic: algebraic geometry

When I was trying to implement the ring interface for Oscar, I stumbled upon the following oddity: ```promote_rule(fmpz, Int)``` gives ```fmpz``` as expected. But ```promote_rule(gfp_elem, Int)``` returns ```Union{}```. That's not...

triage

I try to compute the tangent vector fields to an A_2-singularity using this code: ```julia using Oscar R, var = QQ["x","y","z"] n = length(var) f = var[1]^2 + var[2]^2 +...

triage

An attempt to make the specialized functionality in Singular for zero dimensional ideals available. This seemed to be useful for @simonbrandhorst in some examples, but now I can't even get...

triage

Here's some code to play around with a current example of ours (CC: @simonbrandhorst): ```julia h0 = load("equation.txt") R = parent(h0) x, y = gens(R) h0 = evaluate(h0, [y, x])...

enhancement

Do `I = load("non_radical_ideal.txt")` with [this file](https://github.com/oscar-system/Oscar.jl/files/15250452/non_radical_ideal.txt). For me `radical(I)` does not finish, even though, in my opinion, the ideal is rather tame. Interestingly, the following works: ```julia julia> dec...

bug
triage

I'm using generic polynomial rings `S = A[x,y,...]` over other base rings `A`. Now I have the following problem: The arithmetic is rather slow, for instance when multiplying polynomials. The...