Mask rows and/or columns of a 2D array that contain masked values.

Mask whole rows and/or columns of a 2D array that contain masked values. The masking behavior is selected using the axis parameter.

• If axis is None, rows and columns are masked.
• If axis is 0, only rows are masked.
• If axis is 1 or -1, only columns are masked.
Parameters : a : array_like, MaskedArray The array to mask. If not a MaskedArray instance (or if no array elements are masked). The result is a MaskedArray with mask set to nomask (False). Must be a 2D array. axis : int, optional Axis along which to perform the operation. If None, applies to a flattened version of the array. a : MaskedArray A modified version of the input array, masked depending on the value of the axis parameter. NotImplementedError : If input array a is not 2D.

Mask rows of a 2D array that contain masked values.
Mask cols of a 2D array that contain masked values.
Mask where a condition is met.

Notes

The input array’s mask is modified by this function.

Examples

```>>> import numpy.ma as ma
>>> a = np.zeros((3, 3), dtype=np.int)
>>> a[1, 1] = 1
>>> a
array([[0, 0, 0],
[0, 1, 0],
[0, 0, 0]])
>>> a = ma.masked_equal(a, 1)
>>> a
[[0 0 0]
[0 -- 0]
[0 0 0]],
[[False False False]
[False  True False]
[False False False]],
fill_value=999999)
[[0 -- 0]
[-- -- --]
[0 -- 0]],
[[False  True False]
[ True  True  True]
[False  True False]],
fill_value=999999)
```