`numpy.ma.core:MaskedArray.sort`

Signature

def sort(self, axis = -1, kind = None, order = None, endwith = True, fill_value = None, *, stable = False)

Sort the array, in-place

a : array_like: Array to be sorted.
axis : int, optional: Axis along which to sort. If None, the array is flattened before sorting. The default is -1, which sorts along the last axis.
kind : {'quicksort', 'mergesort', 'heapsort', 'stable'}, optional: The sorting algorithm used.
order : list, optional: When a is a structured array, this argument specifies which fields to compare first, second, and so on. This list does not need to include all of the fields.
endwith : {True, False}, optional: Whether missing values (if any) should be treated as the largest values (True) or the smallest values (False) When the array contains unmasked values sorting at the same extremes of the datatype, the ordering of these values and the masked values is undefined.
fill_value : scalar or None, optional: Value used internally for the masked values. If fill_value is not None, it supersedes endwith.
stable : bool, optional: Only for compatibility with np.sort. Ignored.

See sort for notes on the different sorting algorithms.

import numpy as np
a = np.ma.array([1, 2, 5, 4, 3],mask=[0, 1, 0, 1, 0])
a.sort()
a

a = np.ma.array([1, 2, 5, 4, 3],mask=[0, 1, 0, 1, 0])
a.sort(endwith=False)
a

a = np.ma.array([1, 2, 5, 4, 3],mask=[0, 1, 0, 1, 0])
a.sort(endwith=False, fill_value=3)
a