Date: Thu, 09 Oct 2014 11:12:31 +0530 From: suchith <suchithjn22@gmail.com> Subject: [Numpy-discussion] Extracting individual columns in Numpy To: numpy-discussion@scipy.org Message-ID: <54362047.10102@gmail.com> Content-Type: text/plain; charset="utf-8"

How to extract individual columns from a numpy array? For example, consider this script

import numpy as np a = np.array([[1,2,3],[4,5,6],[7,8,9]]) a[0][:] a[:][0]

Now both a[:][0] and a[0][:] are outputting the same result, i.e np.array([1,2,3]). If I want to extract the array [[1],[4],[7]] then what should I do? Is it possible to add this feature? If so, which file(s) should I edit?

I know C,C++ and Python programming and I am new to open-source software development. Please help me.

Try: In [2]: import numpy as np In [3]: a = np.array([[1,2,3],[4,5,6],[7,8,9]]) In [4]: a[0][:] Out[4]: array([1, 2, 3]) In [5]: a[:][0] Out[5]: array([1, 2, 3]) In [6]: a[0,:] Out[6]: array([1, 2, 3]) In [7]: a[:,0] Out[7]: array([1, 4, 7]) Syntax is different for numpy arrays. Regards, Juan