Numpy / Multiplication
Addition
For addition simply use + operator.
""" Operations / Addition and Substraction (+ -)
"""
import numpy as np
A = np.array([
[1, 1],
[2, 2],
])
B = np.array([
[1, 1],
[3, 3],
])
C = np.add(A, B) # first method
D = A + B # second method
assert (C == D).all()
print("A =\n", A)
print("B =\n", B)
print("A + B =\n", C)
"""
A =
[[1 1]
[2 2]]
B =
[[1 1]
[3 3]]
A + B =
[[2 2]
[5 5]]
"""
Multiplication
For element-wise multiplication we use *
""" Operation / Matrix multiplication
For element-wise multiplication we use *
"""
import numpy as np
A = np.array([
[1, 1],
[2, 2],
])
B = np.array([
[1, 1],
[3, 3],
])
C = np.dot(A, B) # first method
D = A @ B # second method
E = A * B # element-wise multiplication
assert (C == D).all()
assert (E[1, 1] == 6)
print("A =\n", A)
print("B =\n", B)
print("A @ A =\n", A @ A)
print("A * A =\n", A * A)
"""
A =
[[1 1]
[2 2]]
B =
[[1 1]
[3 3]]
A @ A =
[[3 3]
[6 6]]
A * A =
[[1 1]
[4 4]]
"""