How to build a numpy array row by row in a for loop?

Question

This is basically what I am trying to do:

array = np.array()       #initialize the array. This is where the error code described below is thrown

for i in xr         


        

Answer 1

Use a list of 1D numpy arrays, or a list of lists, and then convert it to a numpy 2D array (or use more nesting and get more dimensions if you need to).

import numpy as np

a = []
for i in range(5):
    a.append(np.array([1,2,3])) # or a.append([1,2,3])
a = np.asarray(a) # a list of 1D arrays (or lists) becomes a 2D array

print(a.shape)
print(a)