resize! only when needed EulerGravity

[DanielDoehring]

No description provided.

[github-actions]

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 96.42%. Comparing base (a1be62b) to head (14a3365).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #2224   +/-   ##
=======================================
  Coverage   96.42%   96.42%           
=======================================
  Files         486      486           
  Lines       39164    39167    +3     
=======================================
+ Hits        37761    37764    +3     
  Misses       1403     1403           

Flag	Coverage Δ
unittests	96.42% <100.00%> (+<0.01%)	⬆️

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[ranocha]

What is the performance impact of this?

[DanielDoehring]

Hm I guess you only save a couple if-clauses, true. Is more of a semantic change.

[ranocha]

In that case, it would be consistent with the other code to use resize! right before the stuff is used, e.g.,

• Trixi.jl/src/solvers/dgmulti/shock_capturing.jl

  Line 60 in 62e3584

  resize!(alpha, nelements(mesh, dg))

• Trixi.jl/src/solvers/dgsem_tree/indicators_2d.jl

  Line 158 in 62e3584

  resize!(alpha, nelements(dg, cache))

See also #215

[DanielDoehring]

In that case, it would be consistent with the other code to use resize! right before the stuff is used, e.g.,

* https://github.com/trixi-framework/Trixi.jl/blob/62e3584e52da37dbdcdedb5d5737c2ff1e1c4b2d/src/solvers/dgmulti/shock_capturing.jl#L60

* https://github.com/trixi-framework/Trixi.jl/blob/62e3584e52da37dbdcdedb5d5737c2ff1e1c4b2d/src/solvers/dgsem_tree/indicators_2d.jl#L158

See also #215

Hm I am not sure if these should be compared, as there is no resize! for the indicators where this would be naturally placed. I have done this more or less consistent with the other integrators who only resize when necessary.

[ranocha]

It's fine for me to merge this if @sloede agrees