diff options
Diffstat (limited to 'numpy')
| -rw-r--r-- | numpy/ma/core.py | 46 |
1 files changed, 46 insertions, 0 deletions
diff --git a/numpy/ma/core.py b/numpy/ma/core.py index e24cb956c..e10ae98f0 100644 --- a/numpy/ma/core.py +++ b/numpy/ma/core.py @@ -2755,6 +2755,52 @@ class MaskedArray(ndarray): in any order (either C-, Fortran-contiguous, or even discontiguous), unless a copy is required, in which case it will be C-contiguous. + Examples + -------- + + The ``mask`` can be initialized with an array of boolean values + with the same shape as ``data``. + + >>> data = np.arange(6).reshape((2, 3)) + >>> np.ma.MaskedArray(data, mask=[[False, True, False], + ... [False, False, True]]) + masked_array( + data=[[0, --, 2], + [3, 4, --]], + mask=[[False, True, False], + [False, False, True]], + fill_value=999999) + + Alternatively, the ``mask`` can be initialized to homogeneous boolean + array with the same shape as ``data`` by passing in a scalar + boolean value: + + >>> np.ma.MaskedArray(data, mask=False) + masked_array( + data=[[0, 1, 2], + [3, 4, 5]], + mask=[[False, False, False], + [False, False, False]], + fill_value=999999) + + >>> np.ma.MaskedArray(data, mask=True) + masked_array( + data=[[--, --, --], + [--, --, --]], + mask=[[ True, True, True], + [ True, True, True]], + fill_value=999999, + dtype=int64) + + .. note:: + The recommended practice for initializing ``mask`` with a scalar + boolean value is to use ``True``/``False`` rather than + ``np.True_``/``np.False_``. The reason is :attr:`nomask` + is represented internally as ``np.False_``. + + >>> np.False_ is np.ma.nomask + True + """ __array_priority__ = 15 |