np.random.randint() 与 random.randint()区别

第一步，先来看看两者的help信息是如何定义：
help(np.random.randint)：
randint(low, high=None, size=None, dtype=’l’) (return a range of intergers with low or high bounds)
Return random integers from low (inclusive) to high (exclusive). the specified dtype in the “half-open” interval [low, high). If
high is None (the default), then results are from [0, low).
注：range范围前闭后开 [low, high) 或 [0, low)

help(random.randint)
Help on method randint in module random:
randint(a, b) method of random.Random instance
Return random integer in range [a, b], including both end points.（return an integer）
注：range范围前闭后闭 [a, b]

help(np.random.randint)
Help on built-in function randint:

randint(...) method of mtrand.RandomState instance
    randint(low, high=None, size=None, dtype='l')

    Return random integers from `low` (inclusive) to `high` (exclusive).

    Return random integers from the "discrete uniform" distribution of
    the specified dtype in the "half-open" interval [`low`, `high`). If
    `high` is None (the default), then results are from [0, `low`).

    Parameters
    ----------
    low : int
        Lowest (signed) integer to be drawn from the distribution (unless
        ``high=None``, in which case this parameter is one above the
        *highest* such integer).
    high : int, optional
        If provided, one above the largest (signed) integer to be drawn
        from the distribution (see above for behavior if ``high=None``).
    size : int or tuple of ints, optional
        Output shape.  If the given shape is, e.g., ``(m, n, k)``, then
        ``m * n * k`` samples are drawn.  Default is None, in which case a
        single value is returned.
    dtype : dtype, optional
        Desired dtype of the result. All dtypes are determined by their
        name, i.e., 'int64', 'int', etc, so byteorder is not available
        and a specific precision may have different C types depending
        on the platform. The default value is 'np.int'.

        .. versionadded:: 1.11.0

    Returns
    -------
    out : int 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
    --------
    random.random_integers : similar to `randint`, only for the closed
        interval [`low`, `high`], and 1 is the lowest value if `high` is
        omitted. In particular, this other one is the one to use to generate
        uniformly distributed discrete non-integers.

    Examples
    --------
    >>> np.random.randint(2, size=10)
    array([1, 0, 0, 0, 1, 1, 0, 0, 1, 0])
    >>> np.random.randint(1, size=10)
    array([0, 0, 0, 0, 0, 0, 0, 0, 0, 0])

    Generate a 2 x 4 array of ints between 0 and 4, inclusive:

    >>> np.random.randint(5, size=(2, 4))
    array([[4, 0, 2, 1],
           [3, 2, 2, 0]])

>>> help(random.randint)
Help on method randint in module random:

randint(a, b) method of random.Random instance
    Return random integer in range [a, b], including both end points.

第二步举例说明：

>>> random.randint(1,20)
13
>>> np.random.randint(1,20)
1
>>> np.random.randint(1,20,size=3)
array([19, 18,  4])
>>> np.random.randint(1,20,size=(3,4))
array([[ 4,  8,  7, 13],
       [ 8, 19, 16,  1],
       [ 4,  4,  2, 18]])
>>> np.random.randint(20,size=5)
array([ 4, 19, 17, 17,  8])
>>> np.random.randint(1,size=5)
array([0, 0, 0, 0, 0])
>>> np.random.randint(2,size=5)
array([0, 0, 0, 1, 0])

说明：
np.random.randint() 作为numpy库的一种方法，参数更丰富，相比于ranom.randint() 具备size参数可指定outpud的元素的shape属性

np.random.randint() 与 random.randint()区别

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