How to convert two lists into array coordinates in Python?

Question

In Python, how do I build an array of coordinates given 2 lists of axes, such that the output array contains all the possible coordinate pairs?

e.g.

ax1=[1,3,4]
ax2=[a,b]

"""
Code that combines them
"""

Combined_ax1 = [1,3,4,1,3,4,1,3,4]
Combined_ax2 = [a,a,a,b,b,b,c,c,c]

I need this so I can feed combined_ax1 and combined_ax2 into a function without using multiple for loops.

Combined_ax2, Combined_ax1 = zip(*itertools.product(['a', 'b', 'c'], [1, 3, 4])) gets you (1, 3, 4, 1, 3, 4, 1, 3, 4) and ('a', 'a', 'a', 'b', 'b', 'b', 'c', 'c', 'c') — jonrsharpe
– jonrsharpe, Commented Nov 15, 2016 at 17:39

Ébe Isaac · Accepted Answer · 2016-11-15 17:45:19Z

2

This code would get what you require

import itertools

ax1=[1,3,4]
ax2=['a','b']

Combined_ax1, Combined_ax2 = zip(*itertools.product(ax1, ax2))

answered Nov 15, 2016 at 17:45

Ébe Isaac

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Comments

Rishi Rajasekaran · Accepted Answer · 2016-11-15 17:43:41Z

-1

This can be done by using a list comprehension as follows:

cartesian_product = [(x, y) for x in ax1 for y in ax2]

This code sample will return a list of tuples containing all possible pairs of coordinates.

answered Nov 15, 2016 at 17:43

Rishi Rajasekaran

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