SciML / SciML/ComponentArrays.jl

Unexpected behavior of KeepIndex with partitioned axis

Open
#134 0 comments 0 reactions 0 assignees View on GitHub

Nobody has claimed this yet.

Dominant language
Julia
Stars
375
Forks
42
Avg merge
7h 25m
Merged PRs (30d)
17

Description

Currently getpropery and getindex using KeepIndex return different values.

Using the example of #41, I expected the result using KeepIndex to return ComponentVector(boids = <LazyArray>) rather than only the first entry.

    boid = ComponentArray(pos=zeros(2), vel=zeros(2))   
    u0 = ComponentArray(boids=repeat([boid], 2))    
    u0.boids
#2-element LazyArray{ComponentVector{Float64, SubArray{Float64, 1, Vector{Float64}, Tuple{UnitRange{Int64}}, true}, Tuple{Axis{(pos = 1:2, vel = 3:4)}}}}:
# ComponentVector{Float64,SubArray...}(pos = [0.0, 0.0], vel = [0.0, 0.0])
# ComponentVector{Float64,SubArray...}(pos = [0.0, 0.0], vel = [0.0, 0.0])

    u0[KeepIndex(:boids)]
# ComponentVector{Float64}(boids = (pos = [0.0, 0.0], vel = [0.0, 0.0]))

Contributor guide

Open the contributing guide

First steps

  1. Read the whole issue, then the project's contributing guide.
  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

Research direction

Start by reproducing the example from issue #41 and trace KeepIndex through getindex and getproperty for the partitioned boids axis. Compare the returned shape and contents, then add or update coverage so KeepIndex returns the expected two-element ComponentVector result rather than only the first entry.

Written by the indexing model from the issue text.

Assessment

Tech stack
julia
Domain
data
Issue type
Bug
Difficulty
3/5
Estimated time
1-2 days
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
35/100

Get new issues in your inbox

A short digest of beginner-friendly GitHub issues.