verticalTreatment should just be dimensions `nParticles`

[bradyrx]

@pwolfram, I think the dimensions of verticalTreatment should be changed ti just nParticles from (nParticles, Time). Would I be correct in thinking a particle should never transform its mode? I.e., it is only dependent on particle integer.

This becomes an issue when post-processing. In the following example (with trimmed down output):

ds = xr.open_dataset('mpaso.hist.am.lagrPartTrack.0034-01-01_00.00.00.nc')
ds.attrs = ''
print(ds)

<xarray.Dataset>
Dimensions:            (Time: 15, nParticles: 1037200)
Dimensions without coordinates: Time, nParticles
Data variables:
    indexToParticleID  (nParticles) int32 ...
    particleDIC        (Time, nParticles) float64 ...
    verticalTreatment  (Time, nParticles) int32 ...
    xParticle          (Time, nParticles) float64 ...
    xtime              (Time) |S64 ...
    yParticle          (Time, nParticles) float64 ...
    zLevelParticle     (Time, nParticles) float64 ...
    zParticle          (Time, nParticles) float64 ...

If I want to select for just surface floats to slim down the size:

ds = ds.where(ds.verticalTreatment==1, drop=True)
print(ds)

<xarray.Dataset>
Dimensions:            (Time: 15, nParticles: 64825)
Dimensions without coordinates: Time, nParticles
Data variables:
    indexToParticleID  (nParticles, Time) float64 9.724e+05 ... 1.037e+06
    particleDIC        (Time, nParticles) float64 1.923e+03 ... 2.189e+03
    verticalTreatment  (Time, nParticles) float64 1.0 1.0 1.0 ... 1.0 1.0 1.0
    xParticle          (Time, nParticles) float64 1.78e+06 ... -3.444e+06
    xtime              (Time, nParticles) object b'0034-01-02_00:00:00                                             ' ... b'0034-01-30_00:00:00                                             '
    yParticle          (Time, nParticles) float64 -4.414e+06 ... 8.133e+05
    zLevelParticle     (Time, nParticles) float64 -2.637 -1.952 ... -2.345
    zParticle          (Time, nParticles) float64 4.235e+06 ... 5.298e+06

note that indexToParticleID and xtime get converted to different data types and attempt to broadcast to the (Time, nParticles) format of verticalTreatment. If I select just one time slice of verticalTreatment, the where function proceeds as expected:

ds = ds.where(ds.verticalTreatment.isel(Time=0)==1, drop=True)
print(ds)

<xarray.Dataset>
Dimensions:            (Time: 15, nParticles: 64825)
Dimensions without coordinates: Time, nParticles
Data variables:
    indexToParticleID  (nParticles) float64 9.724e+05 9.724e+05 ... 1.037e+06
    particleDIC        (Time, nParticles) float64 1.923e+03 ... 2.189e+03
    verticalTreatment  (Time, nParticles) float64 1.0 1.0 1.0 ... 1.0 1.0 1.0
    xParticle          (Time, nParticles) float64 1.78e+06 ... -3.444e+06
    xtime              (Time, nParticles) object b'0034-01-02_00:00:00                                             ' ... b'0034-01-30_00:00:00                                             '
    yParticle          (Time, nParticles) float64 -4.414e+06 ... 8.133e+05
    zLevelParticle     (Time, nParticles) float64 -2.637 -1.952 ... -2.345
    zParticle          (Time, nParticles) float64 4.235e+06 ... 5.298e+06

[bradyrx]

Actually xtime is still broken in the second example. This might be an xarray issue as well...