Convert Jalali to Gregorian Date & vice versa

ali1k (Ali Khalili) — Sun, 13 May 2007 15:01:56 GMT


#Jalali Date function by Ali Khalili (ali1k AT yahoo DOT com)

#convert Gregorian to Jalali

def gregorianToJalali(year,month,day)

  gDaysInMonth=[31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31]

  jDaysInMonth=[31, 31, 31, 31, 31, 31, 30, 30, 30, 30, 30, 29]

  gy=(year.to_i)-1600

  gm=(month.to_i)-1

  gd=(day.to_i)-1

  jm=0

  jd=0

  jy=0

  gDayNo=365*gy + (gy+3)/4 - (gy+99)/100 +(gy+399)/400

  i=0

  0.upto(gm-1) do |i|

    gDayNo += gDaysInMonth[i]

  end

  if (gm>1 && (gy%4==0 && gy%100!=0) || (gy%400==0))

    #leap and after Feb

    gDayNo=gDayNo+1

  end

  gDayNo +=gd

  jDayNo= gDayNo-79

  #12053=365*33 + 32/4

  jNp=jDayNo/12053

  jDayNo=jDayNo % 12053

  #1461=365*4 +4/4

  jy=979 + 33*jNp + 4*(jDayNo/1461)

  jDayNo %=1461

  if(jDayNo >= 366)

  jy +=(jDayNo-1)/365

  jDayNo =(jDayNo-1)%365

  end

  i=0

  while (i<11 && jDayNo>=jDaysInMonth[i])

    jDayNo -= jDaysInMonth[i]

    i=i+1

  end

   jm=i+1

  jd=jDayNo+1

  puts " #{jy} - #{jm} - #{jd}"

end

#Convert Jalali to Gregorian

def jalaliToGregorian(year,month,day)

  gDaysInMonth=[31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31]

  jDaysInMonth=[31, 31, 31, 31, 31, 31, 30, 30, 30, 30, 30, 29]

  jy=(year.to_i)-979

  jm=(month.to_i)-1

  jd=(day.to_i)-1

  gm=0

  gd=0

  gy=0

  jDayNo=365*jy + (jy/33)*8 + ((jy%33)+3)/4

  0.upto(jm-1)do |i|

  jDayNo +=jDaysInMonth[i]

end

jDayNo +=jd

gDayNo=jDayNo + 79

#146097=365*400 +400/4 - 400/100 +400/400

gy=1600+400*(gDayNo/146097)

gDayNo = gDayNo%146097

leap=true

if(gDayNo >= 36525)

gDayNo =gDayNo-1

#36524 = 365*100 + 100/4 - 100/100

gy +=100* (gDayNo/36524)

gDayNo=gDayNo % 36524

if(gDayNo>=365)

gDayNo =gDayNo+1

else

leap=false

end

end

#1461 = 365*4 + 4/4

gy += 4*(gDayNo/1461)

gDayNo %=1461

if(gDayNo>=366)

leap=false

gDayNo=gDayNo-1

gy +=gDayNo/365

gDayNo=gDayNo %365

end

  i=0

  tmp=0

  while (gDayNo>= (gDaysInMonth[i]+tmp))

    if(i==1 && leap==true)

    tmp=1

    else

    tmp=0

    end

    gDayNo -=gDaysInMonth[i]+tmp

    i=i+1

  end

  gm=i+1

  gd=gDayNo+1

  puts " #{gy} - #{gm} - #{gd}"

end

#Run Program

#gregorianToJalali(*ARGV)

jalaliToGregorian(*ARGV)
DZone Snippets: Farsi code

Convert Jalali to Gregorian Date & vice versa
