mhw_rem_quan_rate_mod.py

import math
import mmap
import sys

# Author: Nozomi Miyamori
# This program is in the Public Domain.

test_quan_table = [2, 1, 1, 1, 1, 0, 0, 0]
test_rate_table = [50, 40, 5, 4, 1, 0, 0, 0]

# usage this_prog.py brem [brem...]
def main():
    quan_exp_base = math.e ** ((1+5**(1/2))/2)

    for i in sys.argv[1:]:
        with open(i, "r+b") as f:
            with mmap.mmap(f.fileno(), 0) as mm:

                if i.endswith('.brem'):
                    rare_thresh = 12.50
                    rare_drop_prob_coef = math.e
                    Qs = slice(0x33,0x33+8)
                    Rs = slice(0x3b,0x3b+8)
                else:
                    rare_thresh = 6.250
                    rare_drop_prob_coef = math.e ** (1/2)
                    Qs = slice(0x52,0x52+0x10)
                    Rs = slice(0x62,0x62+0x10)

                Q = list(mm[Qs])
                R = list(mm[Rs])

                update_quan_rate_table(Q, quan_exp_base, R, rare_thresh, rare_drop_prob_coef)

                mm[Rs] = bytes(R)
                mm[Qs] = bytes(Q)

def argmax(l):
    return max(enumerate(l), key=lambda x: x[1])[0]

def update_quan_rate_table(quan_table, quan_exp_base, rate_table, rare_thresh, rare_drop_prob_coef):
    for k,v in enumerate(quan_table):
        quan_table[k] = max(round(math.log(max(v * rate_table[k], 1), quan_exp_base) * v), v)

    def new_rare_drop_rate(r):
        return round(min(rare_drop_prob_coef * r, rare_thresh))

    S = sum(new_rare_drop_rate(i) - i for i in rate_table if 0 < i <= rare_thresh)
    S2 = sum(i for i in rate_table if i > rare_thresh)

    if S2 == 0:
        return

    for k,v in enumerate(rate_table):
        if 0 < v <= rare_thresh:
            rate_table[k] = new_rare_drop_rate(v)
        else:
            rate_table[k] = rate_table[k] - round(S * v/S2)

    for i in range(sum(rate_table) - 100):
        rate_table[argmax(rate_table)] -= 1

if __name__ == "__main__":
    main()