numpy.ma.count_masked — NumPy v1.13 Manual (original) (raw)
numpy.ma. count_masked(arr, axis=None)[source]¶
Count the number of masked elements along the given axis.
| Parameters: | arr : array_like An array with (possibly) masked elements. axis : int, optional Axis along which to count. If None (default), a flattened version of the array is used. |
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| Returns: | count : int, ndarray The total number of masked elements (axis=None) or the number of masked elements along each slice of the given axis. |
Examples
import numpy.ma as ma a = np.arange(9).reshape((3,3)) a = ma.array(a) a[1, 0] = ma.masked a[1, 2] = ma.masked a[2, 1] = ma.masked a masked_array(data = [[0 1 2] [-- 4 --] [6 -- 8]], mask = [[False False False] [ True False True] [False True False]], fill_value=999999) ma.count_masked(a) 3
When the axis keyword is used an array is returned.
ma.count_masked(a, axis=0) array([1, 1, 1]) ma.count_masked(a, axis=1) array([0, 2, 1])