python - Select all possible subarrays of length n -

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how can 2d array containing possible consecutive sub-arrays of length?

for example, array ['a', 'b', 'c', 'd', 'e'], , n 3, result should be

[['a', 'b', 'c']  ['b', 'c', 'd']  ['c', 'd', 'e']]

i found similar question relating python lists, i'd numpy, need perform on many different arrays, each of large. basically, speed issue here.

third , final no-loop answer:

def substrings(n, x)   return numpy.fromfunction(lambda i, j: x[i + j], (len(x) - n + 1, n),                              dtype=int)

you'll have profile of these solutions find 1 that's performant. if 1 of these solutions best, please select correct answer.


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