numpy.ma.where
-
numpy.ma.where(condition, x=<no value>, y=<no value>)
[source] -
Return a masked array with elements from
x
ory
, depending on condition.Note
When only
condition
is provided, this function is identical tononzero
. The rest of this documentation covers only the case where all three arguments are provided.- Parameters
-
-
conditionarray_like, bool
-
Where True, yield
x
, otherwise yieldy
. -
x, yarray_like, optional
-
Values from which to choose.
x
,y
andcondition
need to be broadcastable to some shape.
-
- Returns
-
-
outMaskedArray
-
An masked array with
masked
elements where the condition is masked, elements fromx
wherecondition
is True, and elements fromy
elsewhere.
-
See also
-
numpy.where
-
Equivalent function in the top-level NumPy module.
-
nonzero
-
The function that is called when x and y are omitted
Examples
>>> x = np.ma.array(np.arange(9.).reshape(3, 3), mask=[[0, 1, 0], ... [1, 0, 1], ... [0, 1, 0]]) >>> x masked_array( data=[[0.0, --, 2.0], [--, 4.0, --], [6.0, --, 8.0]], mask=[[False, True, False], [ True, False, True], [False, True, False]], fill_value=1e+20) >>> np.ma.where(x > 5, x, -3.1416) masked_array( data=[[-3.1416, --, -3.1416], [--, -3.1416, --], [6.0, --, 8.0]], mask=[[False, True, False], [ True, False, True], [False, True, False]], fill_value=1e+20)
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Licensed under the 3-clause BSD License.
https://numpy.org/doc/1.19/reference/generated/numpy.ma.where.html