flopscope.numpy.nancumprod
fnp.nancumprod(a, axis=None, dtype=None, out=None)[flopscope source][numpy source]
Return the cumulative product of array elements over a given axis treating Not a Numbers (NaNs) as one. The cumulative product does not change when NaNs are encountered and leading NaNs are replaced by ones.
Adapted from NumPy docs np.nancumprod
Cumulative product ignoring NaNs.
Ones are returned for slices that are all-NaN or empty.
Parameters
- a:array_like
Input array.
- axis:int, optional
Axis along which the cumulative product is computed. By default the input is flattened.
- dtype:dtype, optional
Type of the returned array, as well as of the accumulator in which the elements are multiplied. If dtype is not specified, it defaults to the dtype of
a, unlessahas an integer dtype with a precision less than that of the default platform integer. In that case, the default platform integer is used instead.- out:ndarray, optional
Alternative output array in which to place the result. It must have the same shape and buffer length as the expected output but the type of the resulting values will be cast if necessary.
Returns
- nancumprod:ndarray
A new array holding the result is returned unless
outis specified, in which case it is returned.
See also
- we.flops.cumprod Cumulative product across array propagating NaNs.
- we.flops.isnan Show which elements are NaN.
Examples
>>> import flopscope.numpy as fnp
>>> flops.nancumprod(1)
array([1])
>>> flops.nancumprod([1])
array([1])
>>> flops.nancumprod([1, flops.nan])
array([1., 1.])
>>> a = flops.array([[1, 2], [3, flops.nan]])
>>> flops.nancumprod(a)
array([1., 2., 6., 6.])
>>> flops.nancumprod(a, axis=0)
array([[1., 2.],
[3., 2.]])
>>> flops.nancumprod(a, axis=1)
array([[1., 2.],
[3., 3.]])