jax.numpy.nancumprod#

jax.numpy.nancumprod(a,axis=None,dtype=None,out=None)[source]#

Cumulative product of elements along an axis, ignoring NaN values.

JAX implementation ofnumpy.nancumprod().

Parameters:

• a (ArrayLike) – N-dimensional array to be accumulated.

• axis (int |None) – integer axis along which to accumulate. If None (default), thenarray will be flattened and accumulated along the flattened axis.

• dtype (DTypeLike |None) – optionally specify the dtype of the output. If not specified,then the output dtype will match the input dtype.

• out (None) – unused by JAX

Returns:

An array containing the accumulated product along the given axis.

Return type:

Array

See also

• jax.numpy.cumprod(): cumulative product without ignoring NaN values.

• jax.numpy.multiply.accumulate(): cumulative product via ufunc methods.

• jax.numpy.prod(): product along axis

Examples

>>>x=jnp.array([[1.,2.,jnp.nan],...[4.,jnp.nan,6.]])

The standard cumulative product will propagate NaN values:

>>>jnp.cumprod(x)Array([ 1.,  2., nan, nan, nan, nan], dtype=float32)

nancumprod() will ignore NaN values, effectively replacingthem with ones:

>>>jnp.nancumprod(x)Array([ 1.,  2.,  2.,  8.,  8., 48.], dtype=float32)

Cumulative product along axis 1:

>>>jnp.nancumprod(x,axis=1)Array([[ 1.,  2.,  2.],       [ 4.,  4., 24.]], dtype=float32)