3
h+                 @   st   d dl Z d dlmZ ddlmZ ddlmZ dddd	gZd
d Zdd ZdddZ	dddZ
dddZddd	ZdS )    N)normalize_axis_index   )_ni_support)	_nd_imagefourier_gaussianfourier_uniformfourier_ellipsoidfourier_shiftc             C   s   | d krH|j jtjtjtjgkr4tj|j|j d} qtj|jtjd} nRt| tkr| tjtjtjtjgkrtt	dtj|j| d} n| j|jkrt	d| S )N)dtypezoutput type not supportedzoutput shape not correct)
r
   typenumpy	complex64
complex128Zfloat32zerosshapefloat64RuntimeError)outputinput r   6/tmp/pip-build-riy7u7_k/scipy/scipy/ndimage/fourier.py_get_output_fourier(   s    

r   c             C   s   | d krD|j jtjtjgkr0tj|j|j d} qtj|jtjd} nJt| tkrz| tjtjgkrhtdtj|j| d} n| j|jkrtd| S )N)r
   zoutput type not supportedzoutput shape not correct)r
   r   r   r   r   r   r   r   )r   r   r   r   r   _get_output_fourier_complex9   s    r   c             C   sf   t j| } t|| }t|| j}tj|| j}t j|t jd}|jj	sN|j
 }tj| ||||d |S )a"  
    Multidimensional Gaussian fourier filter.

    The array is multiplied with the fourier transform of a Gaussian
    kernel.

    Parameters
    ----------
    input : array_like
        The input array.
    sigma : float or sequence
        The sigma of the Gaussian kernel. If a float, `sigma` is the same for
        all axes. If a sequence, `sigma` has to contain one value for each
        axis.
    n : int, optional
        If `n` is negative (default), then the input is assumed to be the
        result of a complex fft.
        If `n` is larger than or equal to zero, the input is assumed to be the
        result of a real fft, and `n` gives the length of the array before
        transformation along the real transform direction.
    axis : int, optional
        The axis of the real transform.
    output : ndarray, optional
        If given, the result of filtering the input is placed in this array.
        None is returned in this case.

    Returns
    -------
    fourier_gaussian : ndarray
        The filtered input.

    Examples
    --------
    >>> from scipy import ndimage, misc
    >>> import numpy.fft
    >>> import matplotlib.pyplot as plt
    >>> fig, (ax1, ax2) = plt.subplots(1, 2)
    >>> plt.gray()  # show the filtered result in grayscale
    >>> ascent = misc.ascent()
    >>> input_ = numpy.fft.fft2(ascent)
    >>> result = ndimage.fourier_gaussian(input_, sigma=4)
    >>> result = numpy.fft.ifft2(result)
    >>> ax1.imshow(ascent)
    >>> ax2.imshow(result.real)  # the imaginary part is an artifact
    >>> plt.show()
    )r
   r   )r   asarrayr   r   ndimr   _normalize_sequencer   flags
contiguouscopyr   fourier_filter)r   sigmanaxisr   Zsigmasr   r   r   r   H   s    /

c             C   sf   t j| } t|| }t|| j}tj|| j}t j|t jd}|jj	sN|j
 }tj| ||||d |S )a$  
    Multidimensional uniform fourier filter.

    The array is multiplied with the Fourier transform of a box of given
    size.

    Parameters
    ----------
    input : array_like
        The input array.
    size : float or sequence
        The size of the box used for filtering.
        If a float, `size` is the same for all axes. If a sequence, `size` has
        to contain one value for each axis.
    n : int, optional
        If `n` is negative (default), then the input is assumed to be the
        result of a complex fft.
        If `n` is larger than or equal to zero, the input is assumed to be the
        result of a real fft, and `n` gives the length of the array before
        transformation along the real transform direction.
    axis : int, optional
        The axis of the real transform.
    output : ndarray, optional
        If given, the result of filtering the input is placed in this array.
        None is returned in this case.

    Returns
    -------
    fourier_uniform : ndarray
        The filtered input.

    Examples
    --------
    >>> from scipy import ndimage, misc
    >>> import numpy.fft
    >>> import matplotlib.pyplot as plt
    >>> fig, (ax1, ax2) = plt.subplots(1, 2)
    >>> plt.gray()  # show the filtered result in grayscale
    >>> ascent = misc.ascent()
    >>> input_ = numpy.fft.fft2(ascent)
    >>> result = ndimage.fourier_uniform(input_, size=20)
    >>> result = numpy.fft.ifft2(result)
    >>> ax1.imshow(ascent)
    >>> ax2.imshow(result.real)  # the imaginary part is an artifact
    >>> plt.show()
    )r
   r   )r   r   r   r   r   r   r   r   r   r   r   r   r   )r   sizer!   r"   r   sizesr   r   r   r      s    /

c             C   sf   t j| } t|| }t|| j}tj|| j}t j|t jd}|jj	sN|j
 }tj| ||||d |S )a  
    Multidimensional ellipsoid Fourier filter.

    The array is multiplied with the fourier transform of a ellipsoid of
    given sizes.

    Parameters
    ----------
    input : array_like
        The input array.
    size : float or sequence
        The size of the box used for filtering.
        If a float, `size` is the same for all axes. If a sequence, `size` has
        to contain one value for each axis.
    n : int, optional
        If `n` is negative (default), then the input is assumed to be the
        result of a complex fft.
        If `n` is larger than or equal to zero, the input is assumed to be the
        result of a real fft, and `n` gives the length of the array before
        transformation along the real transform direction.
    axis : int, optional
        The axis of the real transform.
    output : ndarray, optional
        If given, the result of filtering the input is placed in this array.
        None is returned in this case.

    Returns
    -------
    fourier_ellipsoid : ndarray
        The filtered input.

    Notes
    -----
    This function is implemented for arrays of rank 1, 2, or 3.

    Examples
    --------
    >>> from scipy import ndimage, misc
    >>> import numpy.fft
    >>> import matplotlib.pyplot as plt
    >>> fig, (ax1, ax2) = plt.subplots(1, 2)
    >>> plt.gray()  # show the filtered result in grayscale
    >>> ascent = misc.ascent()
    >>> input_ = numpy.fft.fft2(ascent)
    >>> result = ndimage.fourier_ellipsoid(input_, size=20)
    >>> result = numpy.fft.ifft2(result)
    >>> ax1.imshow(ascent)
    >>> ax2.imshow(result.real)  # the imaginary part is an artifact
    >>> plt.show()
    )r
      )r   r   r   r   r   r   r   r   r   r   r   r   r   )r   r#   r!   r"   r   r$   r   r   r   r      s    3

c             C   sd   t j| } t|| }t|| j}tj|| j}t j|t jd}|jj	sN|j
 }tj| |||| |S )a  
    Multidimensional Fourier shift filter.

    The array is multiplied with the Fourier transform of a shift operation.

    Parameters
    ----------
    input : array_like
        The input array.
    shift : float or sequence
        The size of the box used for filtering.
        If a float, `shift` is the same for all axes. If a sequence, `shift`
        has to contain one value for each axis.
    n : int, optional
        If `n` is negative (default), then the input is assumed to be the
        result of a complex fft.
        If `n` is larger than or equal to zero, the input is assumed to be the
        result of a real fft, and `n` gives the length of the array before
        transformation along the real transform direction.
    axis : int, optional
        The axis of the real transform.
    output : ndarray, optional
        If given, the result of shifting the input is placed in this array.
        None is returned in this case.

    Returns
    -------
    fourier_shift : ndarray
        The shifted input.

    Examples
    --------
    >>> from scipy import ndimage, misc
    >>> import matplotlib.pyplot as plt
    >>> import numpy.fft
    >>> fig, (ax1, ax2) = plt.subplots(1, 2)
    >>> plt.gray()  # show the filtered result in grayscale
    >>> ascent = misc.ascent()
    >>> input_ = numpy.fft.fft2(ascent)
    >>> result = ndimage.fourier_shift(input_, shift=200)
    >>> result = numpy.fft.ifft2(result)
    >>> ax1.imshow(ascent)
    >>> ax2.imshow(result.real)  # the imaginary part is an artifact
    >>> plt.show()
    )r
   )r   r   r   r   r   r   r   r   r   r   r   r   r	   )r   shiftr!   r"   r   Zshiftsr   r   r   r	      s    .

r'   )r'   r'   Nr'   r'   )r'   r'   Nr'   r'   )r'   r'   Nr'   r'   )r'   r'   N)r   Znumpy.core.multiarrayr    r   r   __all__r   r   r   r   r   r	   r   r   r   r   <module>   s   
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