# -*- coding: utf-8 -*-
"""
Created on Fri Sep 30 08:20:44 2022

@author: Chris
Lab 9 Q3
"""


import matplotlib.pyplot as plt
import numpy as np
from scipy import sparse as sp
from scipy.sparse import linalg as sla
from scipy import linalg as la


A = sp.random(5000,5000, density=0.1)

b = sp.random(5000,1, density=0.1)

x = sla.spsolve(A,b)

c = A @ x - b.A[:,0]

print('L2norm:',la.norm(c,2))