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scipy.stats.

# PermutationMethod

class scipy.stats.PermutationMethod(n_resamples=9999, batch=None, random_state=None, *, rng=None)

  Configuration information for a permutation hypothesis test.

  Instances of this class can be passed into the method parameter of some hypothesis test functions to perform a permutation version of the hypothesis tests.

  Attributes:
    n_resamples int, optional

      The number of resamples to perform. Default is 9999.

    batch int, optional

      The number of resamples to process in each vectorized call to the statistic. Batch sizes >>1 tend to be faster when the statistic is vectorized, but memory usage scales linearly with the batch size. Default is `None`, which processes all resamples in a single batch.

    rng `numpy.random.Generator`, optional

      Pseudorandom number generator used to perform resampling.

      If `rng` is passed by keyword to the initializer or the `rng` attribute is used directly, types other than `numpy.random.Generator` are passed to `numpy.random.default_rng` to instantiate a `Generator` before use. If `rng` is already a `Generator` instance, then the provided instance is used. Specify `rng` for repeatable behavior.

      If this argument is passed by position, if `random_state` is passed by keyword into the initializer, or if the `random_state` attribute is used directly, legacy behavior for `random_state` applies:

      - If `random_state` is None (or `numpy.random`), the `numpy.random.RandomState` singleton is used.

      - If `random_state` is an int, a new `RandomState` instance is used, seeded with `random_state`.

      - If `random_state` is already a `Generator` or `RandomState` instance then that instance is used.

      Changed in version 1.15.0: As part of the SPEC-007 transition from use of `numpy.random.RandomState` to `numpy.random.Generator`, this attribute name was changed from `random_state` to `rng`. For an interim period, both names will continue to work, although only one may be specified at a time. After the interim period, uses of `random_state` will emit warnings. The behavior of both `random_state` and `rng` are outlined above, but only `rng` should be used in new code.