read_array.py
import numpy as np nrows=12 ncols=4 a = np.empty((nrows,ncols)) # create an array knowing its size a[:]=np.NaN # fill the array with NaN fn='array1.txt' f=open(fn, 'r') for row in range(nrows): values=f.readline().split() # read line and split columns for col in range(len(values)): a[row,col]=float(values[col]) # string to float and populate array print a