# Author: Alex Gezerlis

# Numerical Methods in Physics with Python (CUP, 2020)

from triang import testcreate

import numpy as np

def mag(xs):

return np.sqrt(np.sum(xs*xs))

def power(A,kmax=6):

zs = np.ones(A.shape[0])

qs = zs/mag(zs)

for k in range(1,kmax):

zs = A@qs

qs = zs/mag(zs)

print(k,qs)

lam = qs@A@qs

return lam, qs

def testeigone(f,A,indx=0):

eigval, eigvec = f(A)

print(" "); print(eigval); print(eigvec)

npeigvals, npeigvecs = np.linalg.eig(A)

print(" ")

print(npeigvals[indx]); print(npeigvecs[:,indx])

if __name__ == '__main__':

A, bs = testcreate(4,21)

testeigone(power,A)