Creating numpy arrays from existing data

Martin McBride, 2019-09-15
Tags arrays data types
Categories numpy

In this section we will look at how to create numpy arrays from existing data.

From an existing sequence

An easy way to create an array based on data is to use thearray function:

import numpy as np

k1 = [1, 3, 5, 7]
d1 = np.array(k1)

This creates a numpy array d1 based on the list k1:

[1 3 5 7]

You can do this for more dimensions:

k2 = [[10, 20, 30], [40, 50, 60]]
d2 = np.array(k2)


[[10 20 30]
 [40 50 60]]

array will accept any sequence, or numpy array, or anything that behaves like a numpy array.

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If you found this article useful, you might be interested in the book NumPy Recipes or other books by the same author.


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