Numerical Python

Similar to pythons list object.

• All objects in an ndarray must have same datatype
• All math operators work on each individual element in an ''ndarray'

# Properties
a = np.ndarray((2,3,4))
 
a.shape      # Tuple describing shape, e.g. (2,3,4)
a.ndim       # Number of dimensions, equal to len(a.shape), e.g. 3
a.size       # Total number of elements
a.dtype      # Datatype of the elements
a.itemsize   # Size in byte of an element

import numpy as np
 
a1 = np.zeros((4,3,2)) # Create 3-dimensional array with zeros
 
a2 = np.ones((3,4,5)) # Create 3-dimensional array with ones
 
a3 = np.arange(1,10) # Array with values 1..9
a4 = np.arange(10) # Array with values 0..9
a5 = np.arange(1,20,5) # Each 5th value between 1 to 19; [1, 6, 11, 16]