python – 如何从numpy数组中提取多个随机子序列

说我有一个序列s,我想从中选择n个随机子序列,每个子序列的长度为l,并存储在矩阵中.有没有更多的方式来做到这一点

s = np.arange(0, 1000)
n = 5
l = 10
i = np.random.randint(0, len(s)-10, 5)
ss = np.array([s[x:x+l] for x in i])

我们可以利用基于 np.lib.stride_tricks.as_strided的 scikit-image's view_as_windows进行高效的补丁提取,就像这样 –

from skimage.util.shape import view_as_windows

# Get sliding windows (these are simply views)
w = view_as_windows(s, l)

# Index with indices, i for desired output
out = w[i]

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