Function select

dask/array/routines.py:2280–2310

(condlist, choicelist, default=0)

@derived_from(np)
def select(condlist, choicelist, default=0):
    # Making the same checks that np.select
    # Check the size of condlist and choicelist are the same, or abort.
    if len(condlist) != len(choicelist):
        raise ValueError("list of cases must be same length as list of conditions")

    if len(condlist) == 0:
        raise ValueError("select with an empty condition list is not possible")

    choicelist = [asarray(choice) for choice in choicelist]

    try:
        intermediate_dtype = result_type(*choicelist)
    except TypeError as e:
        msg = "Choicelist elements do not have a common dtype."
        raise TypeError(msg) from e

    blockwise_shape = tuple(range(choicelist[0].ndim))

    condargs = [arg for elem in condlist for arg in (elem, blockwise_shape)]
    choiceargs = [arg for elem in choicelist for arg in (elem, blockwise_shape)]

    return blockwise(
        _select,
        blockwise_shape,
        *condargs,
        *choiceargs,
        dtype=intermediate_dtype,
        name="select",
        default=default,
    )


def _partition(total: int, divisor: int) -> tuple[tuple[int, ...], tuple[int, ...]]: