Weighted Average

gistfile1.rb

days = 5                                                                                               
data = [ 25.0000, 24.8750, 24.7813, 24.5938, 24.5000, 24.6250, 25.2188, 27.2500, 26.2500, 26.5938 ]    
                                                                                                       
avg_data = Array.new(data.length) { |pos|                                                              
  tot = 0                                                                                              
  # we check to see if we have enough days left to do a full average - otherwise use whatever we have left
  day_count = days + pos < data.length ? days : data.length - pos                                      
  day_count.times { |day|                                                                              
    tot += data[pos + day] * (day_count - day)                                                         
  }                                                                                                    
  tot / (day_count * (day_count +1) / 2)                                                               
}                                                                                                      
                                                                                                       
puts avg_data