pandas.Series.searchsorted

Series.searchsorted(v, side='left', sorter=None)

Find indices where elements should be inserted to maintain order.

Find the indices into a sorted Series self such that, if the corresponding elements in v were inserted before the indices, the order of self would be preserved.

Parameters:

v : array_like

Values to insert into a.

side : {‘left’, ‘right’}, optional

If ‘left’, the index of the first suitable location found is given. If ‘right’, return the last such index. If there is no suitable index, return either 0 or N (where N is the length of a).

sorter : 1-D array_like, optional

Optional array of integer indices that sort self into ascending order. They are typically the result of np.argsort.

Returns:

indices : array of ints

Array of insertion points with the same shape as v.

See also

Series.sort_values, numpy.searchsorted

Notes

Binary search is used to find the required insertion points.

Examples

>>> x = pd.Series([1, 2, 3])
>>> x
0    1
1    2
2    3
dtype: int64
>>> x.searchsorted(4)
array([3])
>>> x.searchsorted([0, 4])
array([0, 3])
>>> x.searchsorted([1, 3], side='left')
array([0, 2])
>>> x.searchsorted([1, 3], side='right')
array([1, 3])
>>> x.searchsorted([1, 2], side='right', sorter=[0, 2, 1])
array([1, 3])