Python

$ PLOTTING VECTORS

import matplotlib.pyplot as plt

import numpy as np

a1=0.5

a2=0.5

b1=0.2

b2=0.1

ax = plt.axes()

ax.arrow(0, 0, a1, a2, head_width=0.05, head_length=0.05, fc='k', ec='k')

ax.arrow(0, 0, b1, b2, head_width=0.05, head_length=0.05, fc='k', ec='k')

ax.arrow(0, 0, a1+b1,a2+b2, head_width=0.05, head_length=0.1, fc='r', ec='k')

#print(np.sqrt(9))

plt.show()

$ VECTOR CROSS PRODUCT

x = np.array([0,0,1])

y = np.array([0,1,0])

np.cross(x,y)

array([-1, 0, 0])

>>> np.cross(y,x)

array([1, 0, 0])