Question

I have the following method to convert a duration in seconds to hours. For example, 2 hours and a half would result in 2.30 Also, 2 hours and fifteen minutes would result in 2.15. So it outputs number of hours and number of minutes.

I want to modify the method to display 2.5 or 2.25 instead of the above. I need to do it that way to make calculations. For example, if there is a $30/hr salary and employee worked 10 hours and a half, I need to multiply 30*10.5 and not 30*10.30.

def hour_quantity
  unless self.duration.blank?
    hours = (self.duration/60)/60
    minutes = (self.duration/60) % 60
    hours.to_s + '.' + minutes.to_s
  end
end

Answer 1

Jon is correct, as usual. Just use floating point division:

def hour_quantity
  duration / 3600.0
end

When displaying, you might want to round:

puts '%.2f' % hour_quantity

This will give you 2 decimal places, always (e.g. “2.00”, “2.25”, “2.50”). Alternatively:

  puts '%g' % hour_quantity
  puts '%g' % 2.0           #=> "2"
  puts '%g' % 2.25          #=> "2.25"
  puts '%g' % 2.4999999     #=> "2.5"