How to add a row into a 1-D array with python-numpy? [duplicate]

Question

I would like to add a row into a 1-D array with a 2-D array as a result:

import numpy as np
a = np.random.random((3,4))
b = np.array([1,2,3])
c = np.append(b, np.transpose(a[:,2]), axis=0)

But the result is a 1-D array:

array([ 1.        ,  2.        ,  3.        ,  0.77329384,  0.25485223,
    0.56982045])

How can I get the expected result:

array([1. , 2. , 3.  ,],
      [0.77329384, 0.25485223, 0.56982045])

Thanks in advance!

Tony Babarino · Accepted Answer · 2016-04-18 17:53:38Z

1

>>> np.vstack((b, np.transpose(a[:,2])))
array([[ 1.        ,  2.        ,  3.        ],
       [ 0.14942441,  0.75303451,  0.64617275]])

answered Apr 18, 2016 at 17:53

Tony Babarino

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