- API reference
- Index objects
- pandas.Index.isin
pandas.Index.isin#
- Index.isin(values,level=None)[source]#
Return a boolean array where the index values are invalues.
Compute boolean array of whether each index value is found in thepassed set of values. The length of the returned boolean array matchesthe length of the index.
- Parameters:
- valuesset or list-like
Sought values.
- levelstr or int, optional
Name or position of the index level to use (if the index is aMultiIndex).
- Returns:
- np.ndarray[bool]
NumPy array of boolean values.
See also
Series.isin
Same for Series.
DataFrame.isin
Same method for DataFrames.
Notes
In the case ofMultiIndex you must either specifyvalues as alist-like object containing tuples that are the same length as thenumber of levels, or specifylevel. Otherwise it will raise a
ValueError
.Iflevel is specified:
if it is the name of oneand only one index level, use that level;
otherwise it should be a number indicating level position.
Examples
>>>idx=pd.Index([1,2,3])>>>idxIndex([1, 2, 3], dtype='int64')
Check whether each index value in a list of values.
>>>idx.isin([1,4])array([ True, False, False])
>>>midx=pd.MultiIndex.from_arrays([[1,2,3],...['red','blue','green']],...names=('number','color'))>>>midxMultiIndex([(1, 'red'), (2, 'blue'), (3, 'green')], names=['number', 'color'])
Check whether the strings in the ‘color’ level of the MultiIndexare in a list of colors.
>>>midx.isin(['red','orange','yellow'],level='color')array([ True, False, False])
To check across the levels of a MultiIndex, pass a list of tuples:
>>>midx.isin([(1,'red'),(3,'red')])array([ True, False, False])