Fix warning: Series.__getitem__ treating keys as positions is deprecated.

[debnath-d]

Series.getitem treating keys as positions is deprecated.

See: pandas-dev/pandas#53201

See: https://github.com/pandas-dev/pandas/blob/2.1.x/pandas/core/series.py#L1027-L1037

if is_integer(key) and self.index._should_fallback_to_positional:
    warnings.warn(
        # GH#50617
        "Series.__getitem__ treating keys as positions is deprecated. "
        "In a future version, integer keys will always be treated "
        "as labels (consistent with DataFrame behavior). To access "
        "a value by position, use `ser.iloc[pos]`",
        FutureWarning,
        stacklevel=find_stack_level(),
    )
    return self._values[key]

[jonathan-taylor]

I think this is somewhat fixed by casting is_categorical / is_ordinal to np.ndarray

ISLP/ISLP/models/columns.py

Lines 276 to 277 in 47dd59b

	is_categorical = np.asarray(is_categorical)
	is_ordinal = np.asarray(is_ordinal)