How to plot vectors in python using matplotlib

Question

I am taking a course on linear algebra and I want to visualize the vectors in action, such as vector addition, normal vector, so on.

For instance:

Answer 1

What did you expect the following to do?

v1 = [0,0],[M[i,0],M[i,1]]
v1 = [M[i,0]],[M[i,1]]

This is making two different tuples, and you overwrite what you did the first time... Anyway, matplotlib does not understand what a "vector" is in the sense you are using. You have to be explicit, and plot "arrows":

In [5]: ax = plt.axes()

In [6]: ax.arrow(0, 0, *v1, head_width=0.05, head_length=0.1)
Out[6]: 

In [7]: ax.arrow(0, 0, *v2, head_width=0.05, head_length=0.1)
Out[7]: 

In [8]: plt.ylim(-5,5)
Out[8]: (-5, 5)

In [9]: plt.xlim(-5,5)
Out[9]: (-5, 5)

In [10]: plt.show()

Result: