1 d3.time.hour = function(date) {

     2   var offset = date.getTimezoneOffset() / 60;

     3   return new Date((~~(date / 36e5 - offset) + offset) * 36e5);

     4 };

     5 

     6 d3.time.hour.utc = function(date) {

     7   return new Date(~~(date / 36e5) * 36e5);

     8 };