Python: Overflowerror: Math Range Error

To fix it use:

try:
    ans = math.exp(200000)
except OverflowError:
    ans = float('inf')

I think the value gets too large to fit into a double in python which is why you get the OverflowError. The largest value I can compute the exp of on my machine in Python is just sligthly larger than 709.78271.

This may give you a clue why:

Notice the 111442 exponent.

Unfortunately, no one explained what the real solution was. I solved the problem using:

from mpmath import *

You can find the documentation below:

Try np.exp() instead of math.exp()

Numpy handles overflows more gracefully, np.exp(999) results in inf and 1. / (1. + np.exp(999)) therefore simply results in zero

import math 
import numpy as np

print(1-np.exp(-4*1000000*-0.0641515994108))