New utility function to generate a polarities array from a dictionary.

[thurinj]

This functions addresses a need to provide a sorted array for polarities values [-1,0,1] for each stations, from a polarity dictionary.

From the Waveforms+Polarities.py example:

    polarities_dict = {
        "BMR":   0,
        "DIV":  +1,
        "EYAK": +1,
        "PAX":  +1,
        ...
        "PERI": +1,
        "SOLD":  0,
        "TUPA": +1,
        }

    polarities = polarities_array_from_dict(polarities_dict, stations)

it replaces the following loop:

    polarities = np.zeros(len(stations))
    for _i, station in enumerate(stations):
        polarities[_i] = polarities_dict[station.station]

and adds warning prints if there is a discrepancy between the names in stations and polarities_dict.

Mostly straightforward PR, but I am happy to get any feedback if you think it is too redundant (@rmodrak, @ammcpherson, @SeismoFelix).

Planning to merge en Feb 26th.

[rmodrak]

Could you please?
-rename the function something shorter, such as sort_polarities
-place the function in mtuq/misfit/polarity.py

[thurinj]

Hi @rmodrak, thanks for the suggestions.
I went with a shorter name (you're right it was a tad bit too long), but slightly different from your suggestion, since we're not really "sorting" anything per-se (polarities_from_dict). And I moved the function to the polarity misfit.

Should be ready to merge if that's fine for you.