Python: Concatenate 3 arrays

Question

I have theee arrays, and want to combine them

import numpy as np
a = np.array([[1,2,3],[4,5,6]])
b = np.array([[7,8,9],[10,11,12]])
c = np.array([[13,14,15],[16,17,18]])

To get:

array([1,2,3,7,8,9,13,14,15, 4,5,6,10,11,12,16,17,18])

What is the function for this ?

Thanks :)

Divakar · Accepted Answer · 2017-02-27 15:12:18Z

15

Stack those horizontally with np.hstack and flatten with np.ravel -

np.hstack(( a,b,c )).ravel()

answered Feb 27, 2017 at 15:04

Divakar

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Comments

Femkemilene · Accepted Answer · 2019-05-30 13:23:03Z

9

d=np.concatenate((a, b,c), axis=None)

The None parameter ensures that the arrays are flattened before concatenation (the gluing of arrays).

Femkemilene

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answered Apr 30, 2019 at 15:02

Slickmind

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Please, explain why&how your answer works so that It can be more useful to less experiences programmers

The user has provided the input and the output expected, my code gives the output required