Trying to vectorize iterative calculation with numpy

Question

I am trying to make some piece of code more efficient by using the vectorized form in numpy. Let me show you an example so you know what I mean.

Given the following

Answer 1

looking at your result matrix

result = [[ 1, 2,   3, 4,]
          [ 2, 4,   6, 8,]
          [ 4, 8,  12, 16,]
          [ 8, 16, 24, 32,]]

it can be deconstructed into product(elem-wise) of two matrix as

a = [[1, 2, 3, 4],
    [1, 2, 3, 4],
    [1, 2, 3, 4],
    [1, 2, 3, 4]]

b = [[1, 1, 1, 1],
     [2, 2, 2, 2],
     [4, 4, 4, 4]
     [8, 8, 8, 8]]

result = a * b

you can calculate this type of operation using the meshgrid function

aa, bb = np.meshgrid(np.array([1.0, 2.0, 3.0, 4.0]),
                     np.array([1.0, 2.0, 4.0, 8.0]))
result = aa * bb