Golden sequences in Python

golden-seq.py

#!/usr/bin/python3

import sys
import math
import time

phi = (1+math.sqrt(5))/2

print("Phi = " + str(phi))

if len(sys.argv) > 1:
    numbers = sys.argv[1].split(",")
    a, b = int(numbers[0]), int(numbers[1]) 
else:
    a, b = 0, 1

iteration = 0

while True:
    if a and b:
        ratio = b/a
        print("[" + str(iteration) + "] " + str(b) + ":" + str(a) + " | " + str(ratio) + " (" + str(math.fabs(phi - ratio)/phi * 100) + "%)" + "\n"),
    a, b = b, a+b
    iteration += 1
    time.sleep(1)