I have a float list:
[1.0, 2.0, 3.0, 4.0]
How can I reshape this list into a multi-dimensional array like:
[[1.0, 1.0, 1.0], [2.0, 2.0, 2.0], [3.0, 3.0, 3.0], [4.0, 4.0 ,4.0]]
without using a loop? Is it possible using numpy or any other?
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Tomerikoo
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Harisreedhar
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Use `np.broadcast_to(arr[:, None], (4, 3))`. Much better than `repeat`. I'll find the dupe – user3483203 Mar 13 '20 at 21:41
2 Answers
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If you start with a NumPy array, you can use numpy.repeat() and then reshape() to get the array size/shape you want:
> import numpy as np
> a = np.array([1.0, 2.0, 3.0, 4.0])
> np.repeat(a, 3).reshape(-1, 3)
array([[1., 1., 1.],
[2., 2., 2.],
[3., 3., 3.],
[4., 4., 4.]])
Mark
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If you can survive not using numpy:
orig = [1.0, 2.0, 3.0, 4.0]
N = 3
matrix = [[n]*N for n in orig]
tevemadar
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