pandas.Index.fillna

Index.fillna(value=None, downcast=None)

Fill NA/NaN values with the specified value

Parameters:

value : scalar

Scalar value to use to fill holes (e.g. 0). This value cannot be a list-likes.

downcast : dict, default is None

a dict of item->dtype of what to downcast if possible, or the string ‘infer’ which will try to downcast to an appropriate equal type (e.g. float64 to int64 if possible)

Returns:

filled : Index