MAINT: change in pandas.Dataframe.loc

[jklenzing]

FutureWarning: Slicing a positional slice with .loc is not supported, and will raise TypeError in a future version.  Use .loc with labels or .iloc with positions instead.

Deprecated as of pandas 1.1.0, will be removed in pandas 2.0.0 (target Oct 1, 2021)

Line affected:

pysat/pysat/_instrument.py

Line 767 in 09c2e54

self.data.loc[key[0], key[1]] = new

Unit Tests affected:

pysat/tests/test_instrument.py::TestBasics::test_setting_partial_data_by_inputs[changed2-fixed2]
pysat/tests/test_instrument.py::TestBasics2D::test_setting_partial_data_by_inputs[changed2-fixed2]
pysat/tests/test_instrument.py::TestBasicsShiftedFileDates::test_setting_partial_data_by_inputs[changed2-fixed2]

[jklenzing]

Update: this specifically affects cases where:

inst[slice(0, 10), 'doubleMLT'] = 0

which corresponds to the 'changed2-fixed2' conditions in the tests above.

The TypeError that is thrown will handle this correctly by passing the slice through to the index directly, which is the correct way of handling the future operations. Will update the comments around this to close this issue.

[jklenzing]

Closing with merge of #750