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Fonction gaussian_filter1d - module scipy.ndimage

Signature de la fonction gaussian_filter1d

def gaussian_filter1d(input, sigma, axis=-1, order=0, output=None, mode='reflect', cval=0.0, truncate=4.0) 

Description

gaussian_filter1d.__doc__

1-D Gaussian filter.

    Parameters
    ----------
    input : array_like
        The input array.
    sigma : scalar
        standard deviation for Gaussian kernel
    axis : int, optional
        The axis of `input` along which to calculate. Default is -1.
    order : int, optional
        An order of 0 corresponds to convolution with a Gaussian
        kernel. A positive order corresponds to convolution with
        that derivative of a Gaussian.
    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.
    truncate : float, optional
        Truncate the filter at this many standard deviations.
        Default is 4.0.

    Returns
    -------
    gaussian_filter1d : ndarray

    Examples
    --------
    >>> from scipy.ndimage import gaussian_filter1d
    >>> gaussian_filter1d([1.0, 2.0, 3.0, 4.0, 5.0], 1)
    array([ 1.42704095,  2.06782203,  3.        ,  3.93217797,  4.57295905])
    >>> gaussian_filter1d([1.0, 2.0, 3.0, 4.0, 5.0], 4)
    array([ 2.91948343,  2.95023502,  3.        ,  3.04976498,  3.08051657])
    >>> import matplotlib.pyplot as plt
    >>> rng = np.random.default_rng()
    >>> x = rng.standard_normal(101).cumsum()
    >>> y3 = gaussian_filter1d(x, 3)
    >>> y6 = gaussian_filter1d(x, 6)
    >>> plt.plot(x, 'k', label='original data')
    >>> plt.plot(y3, '--', label='filtered, sigma=3')
    >>> plt.plot(y6, ':', label='filtered, sigma=6')
    >>> plt.legend()
    >>> plt.grid()
    >>> plt.show()