2019-09-13 21:34:17 +0200 received badge ● Notable Question (source) 2017-10-11 11:40:13 +0200 received badge ● Popular Question (source) 2017-07-24 14:21:02 +0200 commented question Group action in sage @dan_fulea M is of shape k×n and A,B square matrices of type k×k and n×n. The group is $GL(k,F_{q})$ direct product with $GL(n,F_{q})$ which acts on space of k×n matrices as defined above. I need a stabelizer i.e all the pairs $(A,B) \in GL(k,F_{q}) \times GL(n,F_{q})$ for a fixed M. I think what you stated with points 3 and 4 gives different thing than this. 2017-07-23 19:16:10 +0200 received badge ● Editor (source) 2017-07-23 19:15:46 +0200 commented question Group action in sage @dan_fulea $G_{A}$ is not commutative . Sorry I made a mistake while posting. The definition of action is now corrected. I have defined a function action of the direct product group on space of matrices which produces the required output. Now if you can guide how to get that stabilizer that would be great. 2017-07-22 23:27:59 +0200 asked a question Group action in sage I want to define a group action in sage. The group is a direct product of two general linear groups. The set under action is of matrices and the action is $(A,B) (M)=A^{-1}MB$. Assume all matrices have compatible sizes in order for multiplication. I might need a stabelizer later so I was thinking doing it in GAP but could not figure out how. Any suggestions?