Shortest code to repeat array([x,y,z]) in Python

user_6788640 0
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What is the shortest code to repeat numpy array([x,y,z]) and make array([[x,y,z], [x,y,z], [x,y,z], ...]) which to make the code like shown below:

import numpy as np
p = np.array([1, 2, 3])
n = 10
p_n = np.tile(p, n).reshape(n, 3)

output of the code:

array([[1, 2, 3],
       [1, 2, 3],
       [1, 2, 3],
       [1, 2, 3],
       [1, 2, 3],
       [1, 2, 3],
       [1, 2, 3],
       [1, 2, 3],
       [1, 2, 3],
       [1, 2, 3]])
numpy python
4 Answers

Your code works pretty well. I don't see the point of shorten few characters.

That said here's a (few-character) shorter option

p_n = np.vstack([p]*n)

Note: avoid from numpy import *. Numpy has too many things and it may break some of Python's default functionalities (e.g. bool)

user_42384080

If you already have an array prepared which stores the repeated coordinates, then this is short enough:

p_n[:] = p

It's helpful if you assign to p_n multiple times.

user_129833990

You can also use np.repeat, for example

np.repeat(np.arange(3)[None,:],4,axis=0)
user_83668050

Given array p and scaling number n, shortest one would be (without any function to help it make it a short one) -

p_n = p+[[0]]*n

Sample run -

In [17]: p+[[0]]*n
Out[17]: 
array([[1, 2, 3],
       [1, 2, 3],
       [1, 2, 3],
       [1, 2, 3],
       [1, 2, 3],
       [1, 2, 3],
       [1, 2, 3],
       [1, 2, 3],
       [1, 2, 3],
       [1, 2, 3]])
user_32938810
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