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Fonction maximum_filter1d - module scipy.ndimage

Signature de la fonction maximum_filter1d

def maximum_filter1d(input, size, axis=-1, output=None, mode='reflect', cval=0.0, origin=0) 

Description

maximum_filter1d.__doc__

Calculate a 1-D maximum filter along the given axis.

    The lines of the array along the given axis are filtered with a
    maximum filter of given size.

    Parameters
    ----------
    input : array_like
        The input array.
    size : int
        Length along which to calculate the 1-D maximum.
    axis : int, optional
        The axis of `input` along which to calculate. Default is -1.
    output : array or dtype, optional
        The array in which to place the output, or the dtype of the
        returned array. By default an array of the same dtype as input
        will be created.
    mode : {'reflect', 'constant', 'nearest', 'mirror', 'wrap'}, optional
        The `mode` parameter determines how the input array is extended
        beyond its boundaries. Default is 'reflect'. Behavior for each valid
        value is as follows:
    
        'reflect' (`d c b a | a b c d | d c b a`)
            The input is extended by reflecting about the edge of the last
            pixel. This mode is also sometimes referred to as half-sample
            symmetric.
    
        'constant' (`k k k k | a b c d | k k k k`)
            The input is extended by filling all values beyond the edge with
            the same constant value, defined by the `cval` parameter.
    
        'nearest' (`a a a a | a b c d | d d d d`)
            The input is extended by replicating the last pixel.
    
        'mirror' (`d c b | a b c d | c b a`)
            The input is extended by reflecting about the center of the last
            pixel. This mode is also sometimes referred to as whole-sample
            symmetric.
    
        'wrap' (`a b c d | a b c d | a b c d`)
            The input is extended by wrapping around to the opposite edge.
    
        For consistency with the interpolation functions, the following mode
        names can also be used:
    
        'grid-mirror'
            This is a synonym for 'reflect'.
    
        'grid-constant'
            This is a synonym for 'constant'.
    
        'grid-wrap'
            This is a synonym for 'wrap'.
    cval : scalar, optional
        Value to fill past edges of input if `mode` is 'constant'. Default
        is 0.0.
    origin : int, optional
        Controls the placement of the filter on the input array's pixels.
        A value of 0 (the default) centers the filter over the pixel, with
        positive values shifting the filter to the left, and negative ones
        to the right.

    Returns
    -------
    maximum1d : ndarray, None
        Maximum-filtered array with same shape as input.
        None if `output` is not None

    Notes
    -----
    This function implements the MAXLIST algorithm [1]_, as described by
    Richard Harter [2]_, and has a guaranteed O(n) performance, `n` being
    the `input` length, regardless of filter size.

    References
    ----------
    .. [1] http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.42.2777
    .. [2] http://www.richardhartersworld.com/cri/2001/slidingmin.html

    Examples
    --------
    >>> from scipy.ndimage import maximum_filter1d
    >>> maximum_filter1d([2, 8, 0, 4, 1, 9, 9, 0], size=3)
    array([8, 8, 8, 4, 9, 9, 9, 9])