python - slicing arrays in numpy/scipy -

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i have array like:

a = array([[1,2,3],[3,4,5],[4,5,6]])

what's efficient way slice out 1x2 array out of has first 2 columns of "a"?

i.e.,

array([[2,3],[4,5],[5,6]]) in case.

thanks.

two dimensional numpy arrays indexed using a[i,j] (not a[i][j]), can use same slicing notation numpy arrays , matrices can ordinary matrices in python (just put them in single []):

 >>> numpy import array >>> = array([[1,2,3],[3,4,5],[4,5,6]]) >>> a[:,1:] array([[2, 3],        [4, 5],        [5, 6]])

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