1 d3.time.hours = d3_time_range(d3.time.hour, d3_time_hoursStep, function(date) {

     2   return date.getHours();

     3 });

     4 

     5 d3.time.hours.utc = d3_time_range(d3.time.hour.utc, d3_time_hoursStep, function(date) {

     6   return date.getUTCHours();

     7 });

     8 

     9 function d3_time_hoursStep(date) {

    10   date.setTime(date.getTime() + 36e5);

    11 }