Method to convert between Western calendar and Japanese calendar

background

--I just wrote

code

def convert_year_to_wareki(year):
    wareki_start_year = {
        'Meiji': 1868, 'Taisho': 1912, 'Showa': 1926, 'Heisei': 1989, 'Reiwa': 2019
    }
    if year < wareki_start_year['Taisho']:
        return f"(Meiji{year - wareki_start_year['Meiji'] + 1}Year)"
    elif year == wareki_start_year['Taisho']:
        return f"(Meiji{year - wareki_start_year['Meiji'] + 1}Year/Taisho{year - wareki_start_year['Taisho'] + 1}Year)"
    elif year < wareki_start_year['Showa']:
        return f"(Taisho{year - wareki_start_year['Taisho'] + 1}Year)"
    elif year == wareki_start_year['Showa']:
        return f"(Taisho{year - wareki_start_year['Taisho'] + 1}Year/Showa{year - wareki_start_year['Showa'] + 1}Year)"
    elif year < wareki_start_year['Heisei']:
        return f"(Showa{year - wareki_start_year['Showa'] + 1}Year)"
    elif year == wareki_start_year['Heisei']:
        return f"(Showa{year - wareki_start_year['Showa'] + 1}Year/Heisei{year - wareki_start_year['Heisei'] + 1}Year)"
    elif year < wareki_start_year['Reiwa']:
        return f"(Heisei{year - wareki_start_year['Heisei'] + 1}Year)"
    elif year == wareki_start_year['Reiwa']:
        return f"(Heisei{year - wareki_start_year['Heisei'] + 1}Year/Reiwa{year - wareki_start_year['Reiwa'] + 1}Year)"
    else:
        return f"(Reiwa{year - wareki_start_year['Reiwa'] + 1}Year)"

reference

• https://qiita.com/BigFly3/items/7d6bcf649bedc2b91d3e

   year2Wareki(year){
      let wYear = ''
      let gen = ''
      if(year > 2018){
        wYear = year-2018
        gen = 'Reiwa'
      }else if(year > 1988){
        wYear= year-1988
        gen = 'Heisei'
      }else if(year > 1925){
        wYear = year-1925
        gen = 'Showa'
      }else if(year > 1911){
        wYear = year-1911
        gen = 'Taisho'
      }else if(year > 1867){
        wYear = year-1867
        gen = 'Meiji'
      }
      if(wYear === 1) wYear = 'Former'
      return gen !== '' ? gen + wYear + 'Year' : false
    },

• https://qiita.com/slangsoft/items/700f136c625344d6af80 --It also supports Reiwa.
• https://algorithm.joho.info/programming/python/erajp-py/ --This module did not support Reiwa.

def convert_to_wareki(d: datetime.date) -> str:
    dt_native = datetime.datetime.combine(d, datetime.time())
    return strjpftime(dt_native, f"{d.year}Year(%O%EYear) {d.month}Month{d.day}Day")

2020(2020)January 1

• https://note.com/shimakaze_soft/n/n725edcf789cf