戦果係数を自動で検出する試み

autodetect.py

#!/usr/bin/env python
# -*- coding:utf-8 -*-
from collections import Counter
import itertools
import math


CE = [8931, 1201, 1156, 5061, 4569, 4732, 3779, 4568, 5695, 4619, 4912, 5669, 6586]


data = (
    (1, 337718798),
    (2, 290021904),
    (3, 927964716),
    (4, 826824516),
    (5, 817140688),
    (6, 618849040),
    (7, 731035312),
    (8, 881267080),
    (9, 705626154),
    (10, 719657120),
    (11, 797446892),
    (12, 925227624),
    (13, 1241105346),
    (14, 164909310),
    (15, 150753960),
    (16, 648597516),
    (17, 574405542),
    (18, 594244560),
    (19, 474392986),
    (20, 566715216),
)

tmp_set = set()

for rank, value in data:
    tmp_set.add(int(value / CE[rank % 13]))

gcd_list = []

for a, b in itertools.permutations(tmp_set, 2):
    gcd_list.append(math.gcd(a, b))

counter = Counter([x for x in gcd_list if 0 < x < 100])

#print(len(gcd_list))
#print(counter)
print(u'戦果係数は {:d} です'.format(counter.most_common(1)[0][0]))

Calculator.java

import java.math.BigInteger;
import java.util.*;
import java.util.stream.Collectors;

public class Calculator {
    private static final int[] RANKING_RATE_MAGIC_NUMBERS =
            {8931, 1201, 1156, 5061, 4569, 4732, 3779, 4568, 5695, 4619, 4912, 5669, 6586};

    public static int detectRateCoefficient(Map<Integer, Long> source) {
        Set<BigInteger> set = new HashSet<>();
        source.entrySet()
                .stream()
                .map(e -> e.getValue() / RANKING_RATE_MAGIC_NUMBERS[e.getKey() % 13])
                .map(BigInteger::valueOf)
                .forEach(set::add);

        List<BigInteger> list = new ArrayList<>(set);
        List<Integer> gcdList = new ArrayList<>();

        while (list.size() > 1) {
            BigInteger a = list.remove(0);
            list.stream()
                    .map(b -> b.gcd(a))
                    .map(BigInteger::intValue)
                    //.filter(i -> i < 100)
                    .forEach(gcdList::add);
        }

        return gcdList.stream()
                .collect(Collectors.groupingBy(e -> e, Collectors.counting()))
                .entrySet()
                .stream()
                .max(Comparator.comparing(Map.Entry::getValue))
                .map(Map.Entry::getKey)
                .orElse(0);
    }
}

組み合わせを作る必要はなく、reduceで収束した最大公約数が戦果係数
rsky/logbook-kai-plugins@ef53a41
rsky/logbook-kai-plugins@48e8d2c