Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

toField() leads to a crash #3172

Open
glenndavis52 opened this issue Apr 6, 2024 · 1 comment
Open

toField() leads to a crash #3172

glenndavis52 opened this issue Apr 6, 2024 · 1 comment

Comments

@glenndavis52
Copy link

input:

Qi  =  toField( QQ[i]/(i^2+1) )

R   = Qi[u,v]

(u + v) / i

output:

-- SIGSEGV
-* stack trace, pid: 12251
 0# 0x000000000064E665 in /usr/bin/M2-binary
 1# 0x000000000064E8D3 in /usr/bin/M2-binary
 2# 0x00007FC88D820760 in /lib64/libc.so.6
 3# 0x00000000009224AF in /usr/bin/M2-binary
...
38# 0x00007FC88E41D9A8 in /lib64/libgc.so.1
39# GC_call_with_stack_base in /lib64/libgc.so.1
40# 0x00007FC88D86BB17 in /lib64/libc.so.6
41# clone in /lib64/libc.so.6
-- end stack trace *-

Without the toField(), all is OK.

I am using:
Macaulay2Web
Macaulay2, version 1.22.0.1

@pzinn
Copy link
Collaborator

pzinn commented Apr 6, 2024

Yes this is the same issue that was reported before in the mailing list. It's my fault, I inadvertently let a PR slip into the web version which has not been tested thoroughly yet, namely, fraction fields of iterated polynomial rings.
In normal M2 you'd just get the error message error: not implemented yet: fraction fields of polynomial rings over rings other than ZZ, QQ, or a finite field. The way to avoid this is to not ask M2 to use the fraction field:

i4 : (u+v)*i^-1

o4 = - i*u - i*v

o4 : Qi[u..v]

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Labels
None yet
Projects
None yet
Development

No branches or pull requests

2 participants