Ask Your Question

Add Numpy array into other Numpy array

asked 2013-07-27 11:21:42 +0200

mresimulator gravatar image

updated 2013-07-27 11:35:16 +0200

Hi experts!!

My code starts with a empty array (POPOPO=np.array([])).

In the next lines, np.array are created (L1, L2, ...). How can it add this new-created-arrays into POPOPO in order to obtain the array POPOPO= [[L1],[L2],...]? Its important to note that L1, L2,.... have different lenght.

Waiting for your answers.

Thanks in advance!

edit retag flag offensive close merge delete


Hello mresimulator, what type of arrays are the L1, L2,.. are they one-dimensional? btw, did you solve the problem already?

jack77 gravatar imagejack77 ( 2013-07-27 20:19:27 +0200 )edit

what did you tried so far to fill the POPOPO array?

jack77 gravatar imagejack77 ( 2013-07-27 21:01:04 +0200 )edit

1 Answer

Sort by ยป oldest newest most voted

answered 2013-08-01 16:36:01 +0200

jack77 gravatar image

updated 2013-08-01 16:39:32 +0200


I do not know, if this construction is useful, but you could do the following:

 import numpy as np

 L1 = np.array( [1,2] )                         
 L2 = np.array( [1,2,3] )
 L3 = np.array( [3,2,2,3] )

 L = np.array( [L1, L2, L3], dtype=object )

 L[0] # will return array([1, 2])

if the number of the basic arrays are not known or is variable,
you could compose a command string and then use

count = 3
cmdstr = "L = np.array(["
for i in range(1, count):   cmdstr = cmdstr+ 'L'+str(i)+','
cmdstr = cmdstr+ 'L'+str(count)
cmdstr = cmdstr+"], dtype=object)"
cmdstr # : 'L = np.array([L1,L2,L3], dtype=object)'

exec(cmdstr) # L will be = array([[1 2], [1 2 3], [3 2 2 3]], dtype=object)

Remark: it did'nt work neither with np.concatenate nor with np.append

edit flag offensive delete link more

Your Answer

Please start posting anonymously - your entry will be published after you log in or create a new account.

Add Answer

Question Tools


Asked: 2013-07-27 11:21:42 +0200

Seen: 612 times

Last updated: Aug 01 '13