python中的循环卷积

Question

Is there a way with Python to perform circular convolution between two 1D arrays, like with Matlab function cconv ? I tried numpy.convolve but it isn't the same, and I can't find an equivalent.

Answer 1

You can try this command : scipy.ndimage.filters.convolve1d

You have an option which is named mode and you can write mode = wrap

With that, you get periodic boundary conditions as padding for the convolution

For example :

result = scipy.ndimage.convolve(image,kernel,mode='wrap')

import numpy as np
image = np.array([[0, 0, 0, 0],
                  [0, 0, 0, 1],
                  [0, 0, 0, 0]])
kernel = np.array([[1, 1, 1],
                    [1, 1, 1],
                    [1, 1, 1]])
from scipy.ndimage import convolve
convolve(image, kernel, mode='wrap')
array([[1, 0, 1, 1],   
       [1, 0, 1, 1],
       [1, 0, 1, 1]])