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Fonction isscalar - module numpy.matlib

Signature de la fonction isscalar

def isscalar(element) 

Description

isscalar.__doc__

    Returns True if the type of `element` is a scalar type.

    Parameters
    ----------
    element : any
        Input argument, can be of any type and shape.

    Returns
    -------
    val : bool
        True if `element` is a scalar type, False if it is not.

    See Also
    --------
    ndim : Get the number of dimensions of an array

    Notes
    -----
    If you need a stricter way to identify a *numerical* scalar, use
    ``isinstance(x, numbers.Number)``, as that returns ``False`` for most
    non-numerical elements such as strings.

    In most cases ``np.ndim(x) == 0`` should be used instead of this function,
    as that will also return true for 0d arrays. This is how numpy overloads
    functions in the style of the ``dx`` arguments to `gradient` and the ``bins``
    argument to `histogram`. Some key differences:

    +--------------------------------------+---------------+-------------------+
    | x                                    |``isscalar(x)``|``np.ndim(x) == 0``|
    +======================================+===============+===================+
    | PEP 3141 numeric objects (including  | ``True``      | ``True``          |
    | builtins)                            |               |                   |
    +--------------------------------------+---------------+-------------------+
    | builtin string and buffer objects    | ``True``      | ``True``          |
    +--------------------------------------+---------------+-------------------+
    | other builtin objects, like          | ``False``     | ``True``          |
    | `pathlib.Path`, `Exception`,         |               |                   |
    | the result of `re.compile`           |               |                   |
    +--------------------------------------+---------------+-------------------+
    | third-party objects like             | ``False``     | ``True``          |
    | `matplotlib.figure.Figure`           |               |                   |
    +--------------------------------------+---------------+-------------------+
    | zero-dimensional numpy arrays        | ``False``     | ``True``          |
    +--------------------------------------+---------------+-------------------+
    | other numpy arrays                   | ``False``     | ``False``         |
    +--------------------------------------+---------------+-------------------+
    | `list`, `tuple`, and other sequence  | ``False``     | ``False``         |
    | objects                              |               |                   |
    +--------------------------------------+---------------+-------------------+

    Examples
    --------
    >>> np.isscalar(3.1)
    True
    >>> np.isscalar(np.array(3.1))
    False
    >>> np.isscalar([3.1])
    False
    >>> np.isscalar(False)
    True
    >>> np.isscalar('numpy')
    True

    NumPy supports PEP 3141 numbers:

    >>> from fractions import Fraction
    >>> np.isscalar(Fraction(5, 17))
    True
    >>> from numbers import Number
    >>> np.isscalar(Number())
    True