numpy.random.random_integers — NumPy v2.3.dev0 Manual (original) (raw)

random.random_integers(low, high=None, size=None)#

Random integers of type numpy.int_ between low and high, inclusive.

Return random integers of type numpy.int_ from the “discrete uniform” distribution in the closed interval [low, _high_]. If high is None (the default), then results are from [1, _low_]. The numpy.int_type translates to the C long integer type and its precision is platform dependent.

This function has been deprecated. Use randint instead.

Deprecated since version 1.11.0.

Parameters:

lowint

Lowest (signed) integer to be drawn from the distribution (unlesshigh=None, in which case this parameter is the highest such integer).

highint, optional

If provided, the largest (signed) integer to be drawn from the distribution (see above for behavior if high=None).

sizeint or tuple of ints, optional

Output shape. If the given shape is, e.g., (m, n, k), thenm * n * k samples are drawn. Default is None, in which case a single value is returned.

Returns:

outint or ndarray of ints

size-shaped array of random integers from the appropriate distribution, or a single such random int if size not provided.

See also

randint

Similar to random_integers, only for the half-open interval [low, high), and 0 is the lowest value if high is omitted.

Notes

To sample from N evenly spaced floating-point numbers between a and b, use:

a + (b - a) * (np.random.random_integers(N) - 1) / (N - 1.)

Examples

np.random.random_integers(5) 4 # random type(np.random.random_integers(5)) <class 'numpy.int64'> np.random.random_integers(5, size=(3,2)) array([[5, 4], # random [3, 3], [4, 5]])

Choose five random numbers from the set of five evenly-spaced numbers between 0 and 2.5, inclusive (i.e., from the set\({0, 5/8, 10/8, 15/8, 20/8}\)):

2.5 * (np.random.random_integers(5, size=(5,)) - 1) / 4. array([ 0.625, 1.25 , 0.625, 0.625, 2.5 ]) # random

Roll two six sided dice 1000 times and sum the results:

d1 = np.random.random_integers(1, 6, 1000) d2 = np.random.random_integers(1, 6, 1000) dsums = d1 + d2

Display results as a histogram:

import matplotlib.pyplot as plt count, bins, ignored = plt.hist(dsums, 11, density=True) plt.show()

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