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#
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"""The module holds Modin partition manager implemented for Ray."""

import numpy as np

from modin.engines.base.frame.partition_manager import PandasFramePartitionManager

import ray


class GenericRayFramePartitionManager(PandasFramePartitionManager):
    """The class implements the interface in `PandasFramePartitionManager`."""

    @classmethod
    def to_numpy(cls, partitions, **kwargs):
        """
        Convert `partitions` into a NumPy array.

        Parameters
        ----------
        partitions : NumPy array
            A 2-D array of partitions to convert to local NumPy array.
        **kwargs : dict
            Keyword arguments to pass to each partition ``.to_numpy()`` call.

        Returns
        -------
        NumPy array
        """
        parts = ray.get(
            [
                obj.apply(lambda df, **kwargs: df.to_numpy(**kwargs)).oid
                for row in partitions
                for obj in row
            ]
        )
        n = partitions.shape[1]
        parts = [parts[i * n : (i + 1) * n] for i in list(range(partitions.shape[0]))]

        arr = np.block(parts)
        return arr
