numpy.unique_inverse#

numpy.unique_inverse(x)[source]#

Find the unique elements of x and indices to reconstruct x.

This function is Array API compatible alternative to:

>>> x = np.array([1, 1, 2])
>>> np.unique(x, return_inverse=True, equal_nan=False)
(array([1, 2]), array([0, 0, 1]))
Parameters:
xarray_like

Input array. It will be flattened if it is not already 1-D.

Returns:
outnamedtuple

The result containing:

  • values - The unique elements of an input array.

  • inverse_indices - The indices from the set of unique elements that reconstruct x.

See also

unique

Find the unique elements of an array.

Examples

>>> import numpy as np
>>> np.unique_inverse([1, 1, 2])
UniqueInverseResult(values=array([1, 2]), inverse_indices=array([0, 0, 1]))