Answer to Question #281736 in Python for abhiman

Question

. Define the following vectors and matrices:

vec1 = np.array([ -1., 4., -9.])

mat1 = np.array([[ 1., 3., 5.], [7., -9., 2.], [4., 6., 8. ]]

Perform the following operations on the vector and matrices given above:

a. You can multiply vectors by constants.

Compute vec2 = (np.pi/4) * vec1

b. The cosine function can be applied to a vector to yield a vector of cosines.

Compute 1 vec2 = np.cos( vec2 )

Answer 1

import numpy as np
vec1 = np.array([ -1., 4., -9.])
mat1 = np.array([[ 1., 3., 5.], [7., -9., 2.], [4., 6., 8. ]])
vec2 = (np.pi/4) * vec1
vec3 = np.cos( vec2 )
print(vec2, vec3)

# Output
# [-0.78539816  3.14159265 -7.06858347] [ 0.70710678 -1.          0.70710678]