simple demo of using bracket and brent to optimize a single-variable function

brent_opt.py

#! /usr/bin/env python
# -*- coding: utf-8 -*-
from scipy.optimize import bracket, brent
from scipy.stats import binom
from math import log, isnan
import sys

_inf = float('inf')
def main():
    n = 100
    for k in range(1, n):
        def f(x, *args):
            p = binom.pmf(k, n, x)
            try:
                assert not isnan(p)
                neg_ln_l = -1 * log(p)
            except:
                neg_ln_l = _inf
            return neg_ln_l
        brac_res = bracket(f, .5)
        brent_res = brent(f, brack=brac_res[:3])
        print("{}\t{}".format(k / n, brent_res))

if __name__ == '__main__':
    main()