pandas_select.label.LabelMask

class LabelMask(cond, axis='columns', level=None, **kwargs)[source]

Select labels where the condition is True.

Parameters
  • cond (bool Series/DataFrame, array-like, or callable) – Select labels where cond is True. If cond is a callable, it is computed on the Index and should return a boolean array.

  • axis (default 'columns') – Axis along which the function is applied, {0 or ‘index’, 1 or ‘columns’}

  • level (optional) – Either the integer position of the level or its name. It should only be set if axis targets a MultiIndex, otherwise a IndexError will be raised.

  • kwargs – If cond is a callable(), additional keyword arguments passed to it.

Notes

If applied to a MultiIndex with level=None, all the levels will be tested.

Examples

>>> df = pd.DataFrame({"A": [1], "B": [1]})
>>> df
   A  B
0  1  1
>>> df[LabelMask([True, False])]
   A
0  1
>>> df[LabelMask(lambda x: x == "A")]
   A
0  1