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import sys
import plot
import math as mth
import cmath as cmt
import numpy as npy
import scipy.linalg as sla
dt = 0.08
iterations = 100
state_num = 3
H = npy.array([[1,0],[0,2]])
if len(sys.argv) == 3:
alpha = complex(sys.argv[1])
beta = complex(sys.argv[2])
def init_state(i):
alpha = 1
beta = 1
if state_num > 1:
alpha = i / state_num
beta = (state_num - i) / state_num
return (alpha, beta)
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)
]
states = []
for i in range(state_num):
(alpha, beta) = init_state(i)
norm = npy.linalg.norm([alpha, beta])
state = npy.array([alpha / norm, beta / norm])
states.append(state)
f = open("data", "w")
for i in range(iterations):
for j in range(state_num):
(phi, theta) = bloch_map(states[j])
coords = sphere2cart(phi, theta)
colour = i / iterations
if state_num > 1:
colour = j / state_num
f.write(f"{coords[0]}; {coords[1]}; {coords[2]}; 0; 0; {colour}\n")
states[j] = time_evolution(states[j])
f.close()
plot.plot(1, iterations, state_num, "anim2d.plt")
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