Function unique_no_structured_arr

dask/array/routines.py:1710–1765

(
    ar, return_index=False, return_inverse=False, return_counts=False
)

def unique_no_structured_arr(
    ar, return_index=False, return_inverse=False, return_counts=False
):
    # A simplified version of `unique`, that allows computing unique for array
    # types that don't support structured arrays (such as cupy.ndarray), but
    # can only compute values at the moment.

    if (
        return_index is not False
        or return_inverse is not False
        or return_counts is not False
    ):
        raise ValueError(
            "dask.array.unique does not support `return_index`, `return_inverse` "
            "or `return_counts` with array types that don't support structured "
            "arrays."
        )

    ar = ar.ravel()

    args = [ar, "i"]
    meta = meta_from_array(ar)

    out = blockwise(np.unique, "i", *args, meta=meta)
    out._chunks = tuple((np.nan,) * len(c) for c in out.chunks)

    out_parts = [out]

    name = f"unique-aggregate-{out.name}"
    dsk = {
        (name, 0): (
            (np.unique,)
            + tuple(
                (
                    (np.concatenate, o.__dask_keys__())
                    if hasattr(o, "__dask_keys__")
                    else o
                )
                for o in out_parts
            )
        )
    }

    dependencies = [o for o in out_parts if hasattr(o, "__dask_keys__")]
    graph = HighLevelGraph.from_collections(name, dsk, dependencies=dependencies)
    chunks = ((np.nan,),)
    out = Array(graph, name, chunks, meta=meta)

    result = [out]

    if len(result) == 1:
        result = result[0]
    else:
        result = tuple(result)

    return result