def set_printoptions(precision=None, threshold=None, edgeitems=None,
    linewidth=None, suppress=None, nanstr=None, infstr=None, formatter=None):
    """
    Set printing options.

    These options determine the way floating point numbers, arrays and
    other NumPy objects are displayed.

    Parameters
    ----------
    precision : int, optional
        Number of digits of precision for floating point output (default 8).
    threshold : int, optional
        Total number of array elements which trigger summarization
        rather than full repr (default 1000).
    edgeitems : int, optional
        Number of array items in summary at beginning and end of
        each dimension (default 3).
    linewidth : int, optional
        The number of characters per line for the purpose of inserting
        line breaks (default 75).
    suppress : bool, optional
        Whether or not suppress printing of small floating point values
        using scientific notation (default False).
    nanstr : str, optional
        String representation of floating point not-a-number (default nan).
    infstr : str, optional
        String representation of floating point infinity (default inf).
    formatter : dict of callables, optional
        If not None, the keys should indicate the type(s) that the respective
        formatting function applies to.  Callables should return a string.
        Types that are not specified (by their corresponding keys) are handled
        by the default formatters.  Individual types for which a formatter
        can be set are::

            - 'bool'
            - 'int'
            - 'timedelta' : a `numpy.timedelta64`
            - 'datetime' : a `numpy.datetime64`
            - 'float'
            - 'longfloat' : 128-bit floats
            - 'complexfloat'
            - 'longcomplexfloat' : composed of two 128-bit floats
            - 'numpy_str' : types `numpy.string_` and `numpy.unicode_`
            - 'str' : all other strings

        Other keys that can be used to set a group of types at once are::

            - 'all' : sets all types
            - 'int_kind' : sets 'int'
            - 'float_kind' : sets 'float' and 'longfloat'
            - 'complex_kind' : sets 'complexfloat' and 'longcomplexfloat'
            - 'str_kind' : sets 'str' and 'numpystr'

    See Also
    --------
    get_printoptions, set_string_function, array2string

    Notes
    -----
    `formatter` is always reset with a call to `set_printoptions`.

    Examples
    --------
    Floating point precision can be set:

    >>> import numpy as np
    >>> np.set_printoptions(precision=4)
    >>> print(np.array([1.123456789]))
    [ 1.1235]

    Long arrays can be summarised:

    >>> np.set_printoptions(threshold=5)
    >>> print(np.arange(10))
    [0 1 2 ..., 7 8 9]

    Small results can be suppressed:

    >>> eps = np.finfo(float).eps
    >>> x = np.arange(4.)
    >>> x**2 - (x + eps)**2
    array([ -4.9304e-32,  -4.4409e-16,   0.0000e+00,   0.0000e+00])
    >>> np.set_printoptions(suppress=True)
    >>> x**2 - (x + eps)**2
    array([-0., -0.,  0.,  0.])

    A custom formatter can be used to display array elements as desired:

    >>> np.set_printoptions(formatter={'all':lambda x: 'int: '+str(-x)})
    >>> x = np.arange(3)
    >>> x
    array([int: 0, int: -1, int: -2])
    >>> np.set_printoptions()  # formatter gets reset
    >>> x
    array([0, 1, 2])

    To put back the default options, you can use:

    >>> np.set_printoptions(edgeitems=3,infstr='inf',
    ... linewidth=75, nanstr='nan', precision=8,
    ... suppress=False, threshold=1000, formatter=None)
    """
    global _summaryThreshold, _summaryEdgeItems, _float_output_precision, _line_width, _float_output_suppress_small, _nan_str, _inf_str, _formatter
    if linewidth is not None:
        _line_width = linewidth
    if threshold is not None:
        _summaryThreshold = threshold
    if edgeitems is not None:
        _summaryEdgeItems = edgeitems
    if precision is not None:
        _float_output_precision = precision
    if suppress is not None:
        _float_output_suppress_small = not not suppress
    if nanstr is not None:
        _nan_str = nanstr
    if infstr is not None:
        _inf_str = infstr
    _formatter = formatter
