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

Orbit() of a matrix group on sets of vectors stopped working in GAP 4.13 #5786

Closed
dimpase opened this issue Aug 31, 2024 · 1 comment · Fixed by #5796
Closed

Orbit() of a matrix group on sets of vectors stopped working in GAP 4.13 #5786

dimpase opened this issue Aug 31, 2024 · 1 comment · Fixed by #5796
Labels
kind: bug Issues describing general bugs, and PRs fixing them regression A bug that only occurs in the branch, not in a release

Comments

@dimpase
Copy link
Member

dimpase commented Aug 31, 2024

Observed behaviour

with GAP 4.13.0 or .1, the following stopped working

gap>   gg:=SpecialUnitaryGroup(4,2);
SU(4,2)
gap>    hl:=Z(2)*[
>                 [0,0,1,0],
>                 [1,1,0,0],
>                 [0,1,0,1],
>                 [0,1,1,0],
>                 [1,1,0,1]];
[ [ 0*Z(2), 0*Z(2), Z(2)^0, 0*Z(2) ], [ Z(2)^0, Z(2)^0, 0*Z(2), 0*Z(2) ], [ 0*Z(2), Z(2)^0, 0*Z(2), Z(2)^0 ], [ 0*Z(2), Z(2)^0, Z(2)^0, 0*Z(2) ], [ Z(2)^0, Z(2)^0, 0*Z(2), Z(2)^0 ] ]
gap>        o216:=Orbit(gg,Set(hl),OnSets);
Error, no method found! For debugging hints type ?Recovery from NoMethodFound
Error, no 1st choice method found for `+' on 2 arguments
The 2nd argument is 'fail' which might point to an earlier problem
 at /mnt/opt/gap/lib/methsel2.g:250 called from
pow * gsy + fct( i ) at /mnt/opt/gap/lib/dicthf.gi:184 called from
hash!.intKeyFun( key ) at /mnt/opt/gap/lib/dict.gi:897 called from
LookupDictionary( ht, x ) at /mnt/opt/gap/lib/dict.gi:886 called from
KnowsDictionary( d, i ) at /mnt/opt/gap/lib/oprt.gi:1024 called from
orbish( G, pnt, gens, acts, act ) at /mnt/opt/gap/lib/oprt.gd:858 called from
...  at *stdin*:8
type 'quit;' to quit to outer loop

Expected behaviour

Orbit gets created (the above commands work with GAP 4.12.2 and earlier)

Copy and paste GAP banner (to tell us about your setup)

 ┌───────┐   GAP 4.13.1 of 2024-06-11
 │  GAP  │   https://www.gap-system.org
 └───────┘   Architecture: amd64
 Configuration:  gmp 6.3.0, GASMAN, readline
 Loading the library and packages ...
 Packages:   Alnuth 3.2.1, AtlasRep 2.1.8, AutPGrp 1.11, CRISP 1.4.6, CTblLib 1.3.9, FactInt 1.6.3, FGA 1.5.0, GAPDoc 1.6.7, IO 4.8.2, IRREDSOL 1.4.4, LAGUNA 3.9.6, Polenta 1.3.10, Polycyclic 2.16, PrimGrp 3.4.4, RadiRoot 2.9, 
             ResClasses 4.7.3, SmallGrp 1.5.3, Sophus 1.27, TomLib 1.2.11, TransGrp 3.6.5, utils 0.84
 Try '??help' for help. See also '?copyright', '?cite' and '?authors'
@dimpase dimpase added the regression A bug that only occurs in the branch, not in a release label Aug 31, 2024
@dimpase
Copy link
Member Author

dimpase commented Sep 5, 2024

we are using this idiom in several places in SageMath, and while cooking up a workaround should be easy, it'd be nice to have it fixed

@dimpase dimpase added the kind: bug Issues describing general bugs, and PRs fixing them label Sep 5, 2024
hulpke added a commit to hulpke/gap that referenced this issue Sep 14, 2024
Use list hashing for lists of integers, not lists of vectors.

This fixes gap-system#5786
hulpke added a commit to hulpke/gap that referenced this issue Sep 14, 2024
Use list hashing for lists of integers, not lists of vectors.

This fixes gap-system#5786
hulpke added a commit that referenced this issue Sep 18, 2024
Use list hashing for lists of integers, not lists of vectors.

This fixes #5786
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Labels
kind: bug Issues describing general bugs, and PRs fixing them regression A bug that only occurs in the branch, not in a release
Projects
None yet
Development

Successfully merging a pull request may close this issue.

1 participant