Source code for maxframe.tensor.random.permutation

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from numbers import Integral
from typing import List

import numpy as np

from maxframe import opcodes
from maxframe.core import EntityData
from maxframe.serialization.serializables import Int32Field, KeyField
from maxframe.tensor.datasource import tensor as astensor
from maxframe.tensor.operators import TensorOperatorMixin
from maxframe.tensor.random.core import TensorRandomMapReduceOperator
from maxframe.tensor.utils import AxisError, gen_random_seeds, validate_axis


def _permutation_on_axis(ar, axis, rs, xp):
    try:
        return rs.permutation(ar, axis=axis)
    except TypeError:
        # numpy starts to support axis from 1.18
        if axis == 0:
            return rs.permutation(ar)
        indices = xp.arange(ar.shape[axis])
        rs.shuffle(indices)
        slc = (slice(None),) * axis + (indices,)
        return ar[slc]


class TensorPermutation(TensorRandomMapReduceOperator, TensorOperatorMixin):
    _op_type_ = opcodes.PERMUTATION

    input = KeyField("input")
    axis = Int32Field("axis")

    reduce_size = Int32Field("reduce_size")

    @classmethod
    def _set_inputs(cls, op: "TensorPermutation", inputs: List[EntityData]):
        super()._set_inputs(op, inputs)
        op.input = op._inputs[0]

    def __call__(self, x):
        return self.new_tensor([x], x.shape, order=x.order)


[docs] def permutation(random_state, x, axis=0, chunk_size=None): r""" Randomly permute a sequence, or return a permuted range. Parameters ---------- x : int or array_like If `x` is an integer, randomly permute ``mt.arange(x)``. If `x` is an array, make a copy and shuffle the elements randomly. axis : int, optional The axis which `x` is shuffled along. Default is 0. chunk_size : : int or tuple of int or tuple of ints, optional Desired chunk size on each dimension Returns ------- out : Tensor Permuted sequence or tensor range. Examples -------- >>> import maxframe.tensor as mt >>> rng = mt.random.RandomState() >>> rng.permutation(10).execute() array([1, 2, 3, 7, 9, 8, 0, 6, 4, 5]) # random >>> rng.permutation([1, 4, 9, 12, 15]).execute() array([ 9, 4, 12, 1, 15]) # random >>> arr = mt.arange(9).reshape((3, 3)) >>> rng.permutation(arr).execute() array([[3, 4, 5], # random [6, 7, 8], [0, 1, 2]]) >>> rng.permutation("abc") Traceback (most recent call last): ... numpy.AxisError: x must be an integer or at least 1-dimensional """ if isinstance(x, (Integral, np.integer)): from maxframe.tensor.datasource import arange x = arange(x, chunk_size=chunk_size) else: x = astensor(x, chunk_size=chunk_size) if x.ndim < 1: raise AxisError("x must be an integer or at least 1-dimensional") axis = validate_axis(x.ndim, axis) seed = gen_random_seeds(1, random_state.to_numpy())[0] op = TensorPermutation(seed=seed, axis=axis, dtype=x.dtype, gpu=x.op.gpu) return op(x)