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Would it be a good idea for `\^` for a digraph and a perm to mean `OnDigraphs`?

Open wilfwilson opened this issue 2 years ago • 4 comments

Sometimes I think it would be nice if D ^ p for a digraph and a permutation gave the same as OnDigraphs(D, p);.

For instance, you'd be able to do things like this:

gap> D := CycleDigraph(5);
<immutable cycle digraph with 5 vertices>
gap> p := (1,5)(2,4);;
gap> D ^ p = DigraphReverse(D);
true

However, I haven't though this through fully, and it feels like the sort of thing that might have some unintended consequences (especially in relation to mutability)... does anyone have any thoughts?

My apologies if this is a duplicate, I'm sure I've talked about this idea with people before.

wilfwilson avatar Apr 23 '23 12:04 wilfwilson

Hi, can I have a look at this issue over the reading week and try implementing it?

devansh2605 avatar Apr 02 '25 13:04 devansh2605

Any progress with this so far? It'd be great to see a pull request that implements and documents it.

mtorpey avatar Apr 23 '25 15:04 mtorpey

In case anyone is trying this again in the VIP, here are some thoughts:

  • It would involve installing a method for \^, in the same way other operations are installed in oper.gi.
  • The method would take a digraph (IsDigraph) and a perm (IsPerm) and return the value of OnDigraphs(D, p).

mtorpey avatar Oct 15 '25 13:10 mtorpey

Completed this issue here

devansh2605 avatar Oct 30 '25 11:10 devansh2605