numpy.random.Generator should be preferred to numpy.random.RandomState

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This rule raises an issue when legacy numpy.random.RandomState is used.

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Using a predictable seed is a common best practice when using NumPy to create reproducible results. To that end, using np.random.seed(number) to set the seed of the global numpy.random.RandomState has been the privileged solution for a long time.

numpy.random.RandomState and its associated methods rely on a global state, which may be problematic when threads or other forms of concurrency are involved. The global state may be altered and the global seed may be reset at various points in the program (for instance, through an imported package or script), which would lead to irreproducible results.

Instead, the preferred best practice to generate reproducible pseudorandom numbers is to instantiate a numpy.random.Generator object with a seed and reuse it in different parts of the code. This avoids the reliance on a global state. Whenever a new seed is needed, a new generator may be created instead of mutating a global state.

Below is the list of legacy functions and their alternatives:

Legacy function name	numpy.random.Generator alternative
numpy.random.RandomState.seed	numpy.random.default_rng
numpy.random.RandomState.rand	numpy.random.Generator.random
numpy.random.RandomState.randn	numpy.random.Generator.standard_normal
numpy.random.RandomState.randint	numpy.random.Generator.integers
numpy.random.RandomState.random_integers	numpy.random.Generator.integers
numpy.random.RandomState.random_sample	numpy.random.Generator.random
numpy.random.RandomState.choice	numpy.random.Generator.choice
numpy.random.RandomState.bytes	numpy.random.Generator.bytes
numpy.random.RandomState.shuffle	numpy.random.Generator.shuffle
numpy.random.RandomState.permutation	numpy.random.Generator.permutation
numpy.random.RandomState.beta	numpy.random.Generator.beta
numpy.random.RandomState.binomial	numpy.random.Generator.binomial
numpy.random.RandomState.chisquare	numpy.random.Generator.chisquare
numpy.random.RandomState.dirichlet	numpy.random.Generator.dirichlet
numpy.random.RandomState.exponential	numpy.random.Generator.exponential
numpy.random.RandomState.f	numpy.random.Generator.f
numpy.random.RandomState.gamma	numpy.random.Generator.gamma
numpy.random.RandomState.geometric	numpy.random.Generator.geometric
numpy.random.RandomState.gumbel	numpy.random.Generator.gumbel
numpy.random.RandomState.hypergeometric	numpy.random.Generator.hypergeometric
numpy.random.RandomState.laplace	numpy.random.Generator.laplace
numpy.random.RandomState.logistic	numpy.random.Generator.logistic
numpy.random.RandomState.lognormal	numpy.random.Generator.lognormal
numpy.random.RandomState.logseries	numpy.random.Generator.logseries
numpy.random.RandomState.multinomial	numpy.random.Generator.multinomial
numpy.random.RandomState.multivariate_normal	numpy.random.Generator.multivariate_normal
numpy.random.RandomState.negative_binomial	numpy.random.Generator.negative_binomial
numpy.random.RandomState.noncentral_chisquare	numpy.random.Generator.noncentral_chisquare
numpy.random.RandomState.noncentral_f	numpy.random.Generator.noncentral_f
numpy.random.RandomState.normal	numpy.random.Generator.normal
numpy.random.RandomState.pareto	numpy.random.Generator.pareto
numpy.random.RandomState.poisson	numpy.random.Generator.poisson
numpy.random.RandomState.power	numpy.random.Generator.power
numpy.random.RandomState.rayleigh	numpy.random.Generator.rayleigh
numpy.random.RandomState.standard_cauchy	numpy.random.Generator.standard_cauchy
numpy.random.RandomState.standard_exponential	numpy.random.Generator.standard_exponential
numpy.random.RandomState.standard_gamma	numpy.random.Generator.standard_gamma
numpy.random.RandomState.standard_normal	numpy.random.Generator.standard_normal
numpy.random.RandomState.standard_t	numpy.random.Generator.standard_t
numpy.random.RandomState.triangular	numpy.random.Generator.triangular
numpy.random.RandomState.uniform	numpy.random.Generator.uniform
numpy.random.RandomState.vonmises	numpy.random.Generator.vonmises
numpy.random.RandomState.wald	numpy.random.Generator.wald
numpy.random.RandomState.weibull	numpy.random.Generator.weibull
numpy.random.RandomState.zipf	numpy.random.Generator.zipf
numpy.random.beta	numpy.random.Generator.beta
numpy.random.binomial	numpy.random.Generator.binomial
numpy.random.bytes	numpy.random.Generator.bytes
numpy.random.chisquare	numpy.random.Generator.chisquare
numpy.random.choice	numpy.random.Generator.choice
numpy.random.dirichlet	numpy.random.Generator.dirichlet
numpy.random.exponential	numpy.random.Generator.exponential
numpy.random.f	numpy.random.Generator.f
numpy.random.gamma	numpy.random.Generator.gamma
numpy.random.geometric	numpy.random.Generator.geometric
numpy.random.gumbel	numpy.random.Generator.gumbel
numpy.random.hypergeometric	numpy.random.Generator.hypergeometric
numpy.random.laplace	numpy.random.Generator.laplace
numpy.random.logistic	numpy.random.Generator.logistic
numpy.random.lognormal	numpy.random.Generator.lognormal
numpy.random.logseries	numpy.random.Generator.logseries
numpy.random.multinomial	numpy.random.Generator.multinomial
numpy.random.multivariate_normal	numpy.random.Generator.multivariate_normal
numpy.random.negative_binomial	numpy.random.Generator.negative_binomial
numpy.random.noncentral_chisquare	numpy.random.Generator.noncentral_chisquare
numpy.random.noncentral_f	numpy.random.Generator.noncentral_f
numpy.random.normal	numpy.random.Generator.normal
numpy.random.pareto	numpy.random.Generator.pareto
numpy.random.permutation	numpy.random.Generator.permutation
numpy.random.poisson	numpy.random.Generator.poisson
numpy.random.power	numpy.random.Generator.power
numpy.random.rand	numpy.random.Generator.random
numpy.random.randint	numpy.random.Generator.integers
numpy.random.randn	numpy.random.Generator.standard_normal
numpy.random.random	numpy.random.Generator.random
numpy.random.random_integers	numpy.random.Generator.integers
numpy.random.random_sample	numpy.random.Generator.random
numpy.random.ranf	numpy.random.Generator.random
numpy.random.rayleigh	numpy.random.Generator.rayleigh
numpy.random.sample	numpy.random.Generator.random
numpy.random.seed	numpy.random.default_rng
numpy.random.shuffle	numpy.random.Generator.shuffle
numpy.random.standard_cauchy	numpy.random.Generator.standard_cauchy
numpy.random.standard_exponential	numpy.random.Generator.standard_exponential
numpy.random.standard_gamma	numpy.random.Generator.standard_gamma
numpy.random.standard_normal	numpy.random.Generator.standard_normal
numpy.random.standard_t	numpy.random.Generator.standard_t
numpy.random.triangular	numpy.random.Generator.triangular
numpy.random.uniform	numpy.random.Generator.uniform
numpy.random.vonmises	numpy.random.Generator.vonmises
numpy.random.wald	numpy.random.Generator.wald
numpy.random.weibull	numpy.random.Generator.weibull
numpy.random.zipf	numpy.random.Generator.zipf

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