BUG/DOC: describe constellation_to_inst naming issues

[jklenzing]

Description

Currently, Constellation.to_inst() appends variable names with strings based on platform, name, etc to each variable name. There are some use cases where this is not desirable.

For simulated spacecraft generated from pysatMissions instruments, multiple spacecraft can be instantiated using 'missions_skyfield' with different TLE inputs. These cannot be combine as each will be appended with the same tag.

To Reproduce this bug:

import datetime as dt

import pysat
import pysatMissions

inclinations = [83.0915, 83.4173]
mean_altitude = 375.0
raan = 0.0
arg_perigee = 0.0
mean_anomaly = 0.0

satellites = []
for i in range(0, 2):
    satellites.append(pysat.Instrument(
        inst_module=pysatMissions.instruments.missions_skyfield, name=names[i],
        inclination=inclinations[i], alt_periapsis=mean_altitude, raan=raan,
        arg_periapsis=arg_perigee, mean_anomaly=mean_anomaly))

constellation = pysat.Constellation(instruments=satellites)
constellation.load(date=dt.datetime(2019, 1, 1))
inst = constellation.to_inst()

compare constellations[0].data, constellations[1].data, and inst.data. The instrument object will only include the last set of positional data from constellation[1].

Test configuration

• OS: Mac 14.7
• Version python 3.12

[jklenzing]

Followup: this can be fixed by renaming the 'platform' and/or 'name' after instantiation. In other words:

names = ['A', 'B']
satellites = []
for i in range(0, 2):
    satellites.append(pysat.Instrument(
        inst_module=pysatMissions.instruments.missions_skyfield, name=names[i],
        inclination=inclinations[i], alt_periapsis=mean_altitude, raan=raan,
        arg_periapsis=arg_perigee, mean_anomaly=mean_anomaly))
    satellites[i].name = names[i]

Apparently you can just rename instrument parameters and pysat is cool with that. I don't know whether this is a feature or a bug, but it should be documented somewhere.