Classe « ndarray »

Méthode numpy.ndarray.item

Signature de la méthode item

Description

item.__doc__

a.item(*args)

    Copy an element of an array to a standard Python scalar and return it.

    Parameters
    ----------
    \*args : Arguments (variable number and type)

        * none: in this case, the method only works for arrays
          with one element (`a.size == 1`), which element is
          copied into a standard Python scalar object and returned.

        * int_type: this argument is interpreted as a flat index into
          the array, specifying which element to copy and return.

        * tuple of int_types: functions as does a single int_type argument,
          except that the argument is interpreted as an nd-index into the
          array.

    Returns
    -------
    z : Standard Python scalar object
        A copy of the specified element of the array as a suitable
        Python scalar

    Notes
    -----
    When the data type of `a` is longdouble or clongdouble, item() returns
    a scalar array object because there is no available Python scalar that
    would not lose information. Void arrays return a buffer object for item(),
    unless fields are defined, in which case a tuple is returned.

    `item` is very similar to a[args], except, instead of an array scalar,
    a standard Python scalar is returned. This can be useful for speeding up
    access to elements of the array and doing arithmetic on elements of the
    array using Python's optimized math.

    Examples
    --------
    >>> np.random.seed(123)
    >>> x = np.random.randint(9, size=(3, 3))
    >>> x
    array([[2, 2, 6],
           [1, 3, 6],
           [1, 0, 1]])
    >>> x.item(3)
    1
    >>> x.item(7)
    0
    >>> x.item((0, 1))
    2
    >>> x.item((2, 2))
    1