calc_tax.py

# -*- coding: utf-8 -*-
# 年収から所得税を計算する

import numpy as np
import sys


# bollowed from : https://qiita.com/hideorder/items/a878a794418ef99b7f19
def CalcTax(income):

    assert income > 0 , print("所得が控除額に届いていません")
    p = [0.05, 0.10, 0.20, 0.23 ,0.33 , 0.40, 0.45]
    bin = [i*10000 for i in [0, 195, 330, 695, 900, 1800, 4000, np.inf]]
    deduction = [0, 97500, 427500, 636000, 1536000, 2796000, 4976000]
    SpecialTax = 0.021
    step = len(p)

    ans = 0
    i = 0
    
    for i in range(step):
        if (income >= bin[i]) and (income < bin[i+1]):
            # 復興特別所得税有無
            ans1 = (income*p[i] - deduction[i]) * (1 + SpecialTax)
            ans2 = (income*p[i] - deduction[i]) * (1)
            
            break
    return ans1, ans2 


if __name__=='__main__':
    
    print('年収を入力してください[万円]')
    income_manyen = float(input())
    income_yen = income_manyen * 10000

    print('経費を入力してください[万円]')
    expenses_manyen = float(input())
    expenses_yen = expenses_manyen * 10000

    # 所得控除
    kouzyo = 120 * 10000

    syotoku = income_yen - expenses_yen - kouzyo
    tax, _  = CalcTax(syotoku)

    print("税金: ", tax)