SSEPCompact.py

From Werner KRAUTH

import math
import random
exponent = 3.0
alpha = 0.5
prefactor = 1.0
NPart = 64; NSites = 2 * NPart
NIter = int(prefactor * NPart ** exponent * math.log(NPart))
NStrob = NIter // 40
Conf = [1] * NPart + [0] * (NSites - NPart)
Active = random.randint (0, NSites - 1)
while Conf[Active] != 1:
    Active = random.randint(0, NSites - 1)
Text = 'Periodic SSEP, N= ' + str(NPart) + ', L= ' + str(NSites)
print(' ' * (NSites// 2 + 1 - len(Text) // 2) + Text + ' ' * (NSites// 2 + 1 - len(Text) // 2))
print('-' * (NSites + 2))
for iter in range(NIter):
    Active = random.randint (0, NSites - 1)
    while Conf[Active] != 1: Active = random.randint(0, NSites - 1)
    Step = random.choice([-1,1])
    NewActive = (Active + Step) % NSites
    if Conf[NewActive] == 0: Conf[Active], Conf[NewActive] = 0, 1
    PP = '|'
    ktot= 0
    for k in range(NSites):
        if Conf[k] == 0:
            PP += ' '
        else:
           ktot += 1
           if ktot != NPart / 2: PP += 'X'
           else: PP += '|'
    if iter % NStrob == 0: print(PP)
print('-' * (NSites + 2))
Text = 'Total time = ' + str(prefactor) +  ' *  N ^ ' + str(exponent) + ' * log N'
print(' ' * (NSites// 2 + 1 - len(Text) // 2) + Text + ' ' * (NSites// 2 + 1 - len(Text) // 2))