Subclassing not working as expected

[rserbitar]

Running the code:

import pandas

class SubclassedSeries(pandas.Series):
    @property
    def _constructor(self):
        return SubclassedSeries

    @property
    def _constructor_expanddim(self):
        return SubclassedDataFrame

    def c(self):
        return 1

class SubclassedDataFrame(pandas.DataFrame):
    @property
    def _constructor(self):
        return SubclassedDataFrame

    @property
    def _constructor_sliced(self):
        return SubclassedSeries


b = SubclassedDataFrame([[1,2,3,4],[2,3,4,5]])
print(b[0].c())

works as expected.

However running:

print(b.ix[1].c())

throws an exception as:

b.ix[1]

returns a Series instance instead of an SublcassedSeries instance as expected.

[jreback]

ok, subclassing is not recommended, see docs here, but would take a pull-request to fully test out the indexers (as this is not currently done).

[sinhrks]

This is already fixed on master (maybe by #12787). Needs tests though.

[kielpins-hp]

The lack of subclassing makes it difficult and/or fragile to extend the package in any way. It's really unfortunate.