Slicing using vectors

[schuler]

Try this:

import numpy as np
n = 100
m = 2
A = np.array(np.random.randint(66, size=(n,m), dtype=np.int32))
i = np.array(np.random.randint(n-4, size=int(0.5*n), dtype=np.int32))
j = i + 4*np.ones(int(0.5*n), dtype=np.int32)
print(i)
print(j)
print(i.shape)
print(j.shape)
extract1_A = np.array(A[i,:])
extract2_A = np.array([ A[x:x+4,:] for x in i])
extract3_A = np.array([ A[x:y,:] for x in i for y in j])
print (extract1_A.shape)
print (extract2_A.shape)
print (extract3_A.shape)

wish everyone happy coding