Velocity and geometry units added to output files.

[JanosJiri]

The units of geometries and velocities are lacking in their respective output files. I've spent time looking for the right units of velocities in ABIN several times (because I always forget) and others in Prague have the same issue. I suggest to add the units of geometries and especially velocities to their respective output files.

The proposed way adds the units to every single geometry/velocity such that if someone greps specific geometries/velocities, the information about the unit is kept. Alternatively, the unit could be added to a header, but this would add one extra line and could break loads of existing scripts grepping from movie.xyz or velocities.xyz. What I propose is left for discussion @danielhollas , but adding this would save a lot of time for many people.

FYI, all the tests are failing because of the added units to the files but I did not mend the tests before (or if) we agree on the precise way of adding them.

[danielhollas]

Thanks! I basically agree with all you wrote, and the approach looks reasonable. I'll think a bit more about the wording/ formatting later today.

[danielhollas]

I would ideally want to avoid using the fixed-width for the integer formatting. I am assuming the compiler complained once you added an extra string after it? Should we move the units at the beginning of the line? Another question, perhaps just units: a.u. would be sufficient? I guess it should be obvious from the context that these units are for velocities?

[JanosJiri]

Thanks for the comment, would you agree on write (UVELOC, '(A,I0)') 'Units: a.u.; Time step: ', time_step? Same for movie.xyz of course.

[danielhollas]

Yep, let's go with that, thanks!

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 92.84%. Comparing base (eef82e1) to head (d4a87f6).
Report is 1 commits behind head on master.

Additional details and impacted files

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  Coverage   92.84%   92.84%           
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  Files          47       47           
  Lines        6761     6761           
  Branches      764      764           
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  Hits         6277     6277           
  Misses        472      472           
  Partials       12       12           

Flag	Coverage Δ
unittests	20.37% <0.00%> (ø)

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Files with missing lines	Coverage Δ
src/analysis.F90	98.85% <100.00%> (ø)

[JanosJiri]

This PR (number 200!) is ready for review @danielhollas.

[danielhollas]

LG, thanks!

Ideally, we'd have consistent headers and include the simulation time in velocities as well, and similarly for forces. But let's leave this for future, I know it was probably very annoying to fixup all the reference files. 😅