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#import plotting
import subprocess
import math as mth
import cmath as cmt
import numpy as npy
import scipy.linalg as sla
alpha = 0
beta = 1
norm = npy.linalg.norm([alpha, beta])
state = npy.array([alpha / norm, beta / norm])
dt = 0.1
iterations = 61
H = npy.array([[2,1j],[-1j,3]])
def time_evolution(state, dt = dt):
return npy.dot(state, sla.expm(-1j * dt * H))
def bloch_map(state):
temp = npy.conj(state[0] / state[1])
theta = 2 * npy.arctan(abs(temp))
phi = cmt.phase(temp)
return (phi, theta)
def sphere2cart(phi, theta):
return [
mth.sin(theta) * mth.cos(phi),
mth.sin(theta) * mth.sin(phi),
-1 * mth.cos(theta)
]
historie = npy.array([bloch_map(state)])
f = open("data", "w")
for i in range(iterations + 1):
historie = npy.vstack([historie,bloch_map(state)])
(phi, theta) = bloch_map(state)
coords = sphere2cart(phi, theta)
f.write(f"{coords[0]}; {coords[1]}; {coords[2]}; {(i + 1) / (iterations + 1)}\n")
state = time_evolution(state)
f.close()
subprocess.run(["gnuplot", "gnuplot.plt"])
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