Simon Christ (May 20 2021 at 13:38): Simon Christ (May 20 2021 at 13:38):is there an easy way to make arithmetic operations of a subtype of AbstractArray and an Array return the other type and not Array?
Júlio Hoffimann (May 20 2021 at 13:42):I was looking into it the other day but got busy with other tasks. I think you need to define a method for Base.similar for your array type. See the SparseArray example here: https://docs.julialang.org/en/v1/manual/interfaces/#man-interface-array
Simon Christ (May 20 2021 at 13:59):This indee makes copy work, but e.g. + returns still an array
Simon Christ (May 20 2021 at 14:00):I guess I'd need promotion rules for that
Michael Abbott (May 20 2021 at 23:41):One way is to overload broadcasting, that's where A+B goes. I don't think promotion rules get used for arrays, although broadcasting has some similar mechanisms to try to decide who wins.
Jonnie Diegelman (May 25 2021 at 14:34):Yeah, it’s best to do it via the broadcasting machinery. I found that trying to handle it directly by dispatch methods is a losing battle due to all the method ambiguities.
Last updated: Nov 27 2025 at 04:44 UTC