business day between 2 date

gistfile1.rb

(((calculate_working_days(20.days.ago ,Time.now, [0,6])/60)/60)/24).to_i


   # wdays is an array with the days of the week
   # to exclude (eg: [0,6] for sunday and saturday )

   def calculate_working_days(d1,d2,wdays)
        diff = d2 - d1
        holidays = 0
        ret = (d2-d1).divmod(7)
        holidays =  ret[0].truncate * wdays.length
        d1 = d2 - ret[1]
        while(d1 <= d2)
                if wdays.include?(d1.wday)
                        holidays += 1
                end
                d1 += 1
        end
        diff - holidays
   end


def business_days_ago(num,start_date=nil)
   # takes the number of days in the past you are looking for
   # like 10 business days ago
   start_date ||= Date.today
   start_day_of_week = start_date.cwday #Date.today.cwday
   ans = 0
   # find the number of weeks
   weeks = num / 5.0
   #puts "yields #{weeks} weeks"
 
   temp_num = num > 5 ? 5 : num
   #puts "first temp num #{temp_num}"
 
   begin
 
     ans += days_to_adjust(start_day_of_week,temp_num)
     #puts "ans in loop #{ans}"
 
     weeks -= 1.0
     #puts "weeks in loop #{weeks}"
 
     temp_num = (weeks >= 1) ? 5 : num % 5
     #puts "temp_num after loop #{temp_num}"
   end while weeks > 0
 
   #puts "#{start_date} - #{num} - #{ans}"
   days_ago = start_date - num - ans
 
 end
 
 
 
 def days_to_adjust(start_day_of_week,num)
   ansr = 0
   case start_day_of_week
   when 1
     if (1..5).include?(num) then ansr += 2 end
   when 2
     if (2..5).include?(num) then ansr += 2 end
   when 3
     if (3..5).include?(num) then ansr += 2 end
   when 4
     if (4..5).include?(num) then ansr += 2 end
   when 5
     if 5 == num then ansr += 2 end
   when 6
     # no adj
   when 7
     if (1..5).include?(num) then ansr += 1 end
   end
   return ansr
 end

business_days_ago(5)