Python - how to resize an array and duplicate the elements-CodePudding

I've got an array like this a = [[1,2,3],[4,5,6],[7,8,9]], and I want to change it tob = [[1,1,2,2,3,3],[1,1,2,2,3,3],[4,4,5,5,6,6],[4,4,5,5,6,6],[7,7,8,8,9,9],[7,7,8,8,9,9]]. I've tried to use numpy.resize() function but after resizing, it gives [[1,2,3,4],[1,2,3,4],[1,2,3,4],[1,2,3,4]]. I can use a for loop to put the numbers at the indexes I need but just wondering if there is any easier way of doing that?

Here is the original array

This is what I want

CodePudding user response：

My initial though was that np.tile would work but in fact what you are looking for is np.repeat twice on two different axes.

Try this runnable example!

#!/usr/bin/env python

import numpy as np
a = [[1,2,3],[4,5,6],[7,8,9]]
b = np.repeat(np.repeat(a, 2, axis=1), 2, axis=0)
b

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