numpy.ma.unique#
- ma.unique(ar1, return_index=False, return_inverse=False)[source]#
Finds the unique elements of an array.
Masked values are considered the same element (masked). The output array is always a masked array. See
numpy.unique
for more details.See also
numpy.unique
Equivalent function for ndarrays.
Examples
>>> import numpy as np >>> a = [1, 2, 1000, 2, 3] >>> mask = [0, 0, 1, 0, 0] >>> masked_a = np.ma.masked_array(a, mask) >>> masked_a masked_array(data=[1, 2, --, 2, 3], mask=[False, False, True, False, False], fill_value=999999) >>> np.ma.unique(masked_a) masked_array(data=[1, 2, 3, --], mask=[False, False, False, True], fill_value=999999) >>> np.ma.unique(masked_a, return_index=True) (masked_array(data=[1, 2, 3, --], mask=[False, False, False, True], fill_value=999999), array([0, 1, 4, 2])) >>> np.ma.unique(masked_a, return_inverse=True) (masked_array(data=[1, 2, 3, --], mask=[False, False, False, True], fill_value=999999), array([0, 1, 3, 1, 2])) >>> np.ma.unique(masked_a, return_index=True, return_inverse=True) (masked_array(data=[1, 2, 3, --], mask=[False, False, False, True], fill_value=999999), array([0, 1, 4, 2]), array([0, 1, 3, 1, 2]))