roelentless

##
# Having two times, group the time by dates in percentages.
# Time and analysis will be done in the timezone the time is passed with.
# Result for time range D1-D5:
# D1      |-----D2------------D3------------D4------|     D5
#          16.67%    32.34%        32.34%     16.67%
def date_range_group(start_time, end_time)
  return nil unless start_time
  return nil unless end_time > start_time
  total = end_time - start_time