Fix variable name from v to v_1

[DanielDoehring]

See #2035 (comment)

[github-actions]

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 96.76%. Comparing base (5593691) to head (408e87e).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #2527   +/-   ##
=======================================
  Coverage   96.76%   96.76%           
=======================================
  Files         512      512           
  Lines       42391    42391           
=======================================
  Hits        41016    41016           
  Misses       1375     1375           

Flag	Coverage Δ
unittests	96.76% <ø> (ø)

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[JoshuaLampert]

In the docstring of CompressibleEulerEquations1D we use $$v_1$$. Wouldn't it make more sense to also use $$v_1$$ everywhere for Navier-Stokes to stay consistent?

[DanielDoehring]

In the docstring of CompressibleEulerEquations1D we use v 1 . Wouldn't it make more sense to also use v 1 everywhere for Navier-Stokes to stay consistent?

Makes sense to me 👍 !

[JoshuaLampert]

Thanks!

[andrewwinters5000]

Just a few minor comments that clarify what is being done

[jlchan]

The v -> v_1 changes seem good to me, but the gradient comments seem like they needs a bit more discussion.

[DanielDoehring]

The v -> v_1 changes seem good to me, but the gradient comments seem like they needs a bit more discussion.

Okay, lets do the following: I strip the gradient stuff from this PR, put everything into #2528 and then we merge here?