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Fonction seterr - module numpy.matlib

Signature de la fonction seterr

def seterr(all=None, divide=None, over=None, under=None, invalid=None) 

Description

seterr.__doc__

    Set how floating-point errors are handled.

    Note that operations on integer scalar types (such as `int16`) are
    handled like floating point, and are affected by these settings.

    Parameters
    ----------
    all : {'ignore', 'warn', 'raise', 'call', 'print', 'log'}, optional
        Set treatment for all types of floating-point errors at once:

        - ignore: Take no action when the exception occurs.
        - warn: Print a `RuntimeWarning` (via the Python `warnings` module).
        - raise: Raise a `FloatingPointError`.
        - call: Call a function specified using the `seterrcall` function.
        - print: Print a warning directly to ``stdout``.
        - log: Record error in a Log object specified by `seterrcall`.

        The default is not to change the current behavior.
    divide : {'ignore', 'warn', 'raise', 'call', 'print', 'log'}, optional
        Treatment for division by zero.
    over : {'ignore', 'warn', 'raise', 'call', 'print', 'log'}, optional
        Treatment for floating-point overflow.
    under : {'ignore', 'warn', 'raise', 'call', 'print', 'log'}, optional
        Treatment for floating-point underflow.
    invalid : {'ignore', 'warn', 'raise', 'call', 'print', 'log'}, optional
        Treatment for invalid floating-point operation.

    Returns
    -------
    old_settings : dict
        Dictionary containing the old settings.

    See also
    --------
    seterrcall : Set a callback function for the 'call' mode.
    geterr, geterrcall, errstate

    Notes
    -----
    The floating-point exceptions are defined in the IEEE 754 standard [1]_:

    - Division by zero: infinite result obtained from finite numbers.
    - Overflow: result too large to be expressed.
    - Underflow: result so close to zero that some precision
      was lost.
    - Invalid operation: result is not an expressible number, typically
      indicates that a NaN was produced.

    .. [1] https://en.wikipedia.org/wiki/IEEE_754

    Examples
    --------
    >>> old_settings = np.seterr(all='ignore')  #seterr to known value
    >>> np.seterr(over='raise')
    {'divide': 'ignore', 'over': 'ignore', 'under': 'ignore', 'invalid': 'ignore'}
    >>> np.seterr(**old_settings)  # reset to default
    {'divide': 'ignore', 'over': 'raise', 'under': 'ignore', 'invalid': 'ignore'}

    >>> np.int16(32000) * np.int16(3)
    30464
    >>> old_settings = np.seterr(all='warn', over='raise')
    >>> np.int16(32000) * np.int16(3)
    Traceback (most recent call last):
      File "<stdin>", line 1, in <module>
    FloatingPointError: overflow encountered in short_scalars

    >>> from collections import OrderedDict
    >>> old_settings = np.seterr(all='print')
    >>> OrderedDict(np.geterr())
    OrderedDict([('divide', 'print'), ('over', 'print'), ('under', 'print'), ('invalid', 'print')])
    >>> np.int16(32000) * np.int16(3)
    30464