Converting NumPy array into Python List structure?

Question

How do I convert a NumPy array to a Python List (for example [[1,2,3],[4,5,6]] ), and do it reasonably fast?

Peter Hansen · Accepted Answer · 2009-12-27 15:36:24Z

up vote 156 down vote accepted

import numpy as np
>>> np.array([[1,2,3],[4,5,6]]).tolist()
[[1, 2, 3], [4, 5, 6]]

answered Dec 27 '09 at 15:31

Peter Hansen

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Peter Mortensen · Answer 2 · 2009-12-28 21:22:09Z

up vote 30 down vote

NumPy arrays have a tolist method:

In [1]: arr=np.array([[1,2,3],[4,5,6]])

In [2]: arr.tolist()
Out[2]: [[1, 2, 3], [4, 5, 6]]

Peter Mortensen

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answered Dec 27 '09 at 15:32

unutbu

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Kongsea · Answer 3 · 2016-07-22 09:04:54Z

up vote 0 down vote

You can also use the list keyword of Python to create a list from the numpy array:

import numpy as np
nda = np.arange(10).reshape(2,5)
ndlist = list(nda)

answered Jul 22 at 9:04

Kongsea

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3 Answers 3