Dim=2 because you're using a 2D array; in the following examples, 3 type of arrays have been defined:
- a vector = 1D array (dim=1)
- a 3x3 matrix = 2D array (dim=2)
- a 3D matrix (equivalent to n "layers" of 2D matrixes) - dim=3
import numpy as np
thrD = np.array([[1,2,3],
[3,4,5],
[1,-2,8]])
print(f"thrD = \n{thrD}")
print(f"thrd dim = {thrD.ndim}\n")
Vector1 = np.array([1,2,3])
Vector2 = np.arange(3)
print(f"Vector1 = {Vector1}")
print(f"Vector2 = {Vector2}")
print(f"vector1 dim = {Vector1.ndim} and vector2 dim = {Vector2.ndim}")
Matrix3D = np.arange(27).reshape(3,3,3)
print(f"Matrix3D = \n{Matrix3D}")
print(f"Matrix3D dim = {Matrix3D.ndim}\n")giving
Output:
thrD =
[[ 1 2 3]
[ 3 4 5]
[ 1 -2 8]]
thrd dim = 2
Vector1 = [1 2 3]
Vector2 = [0 1 2]
vector1 dim = 1 and vector2 dim = 1
Matrix3D =
[[[ 0 1 2]
[ 3 4 5]
[ 6 7 8]]
[[ 9 10 11]
[12 13 14]
[15 16 17]]
[[18 19 20]
[21 22 23]
[24 25 26]]]
Matrix3D dim = 3
