highcharts datetime axis, how to comput correct ti

Question

Let say I want to draw a series where the first point represents the time 11:30 of november 5 2013. I want the time 11:30 to be the same if I look my chart with a browser in a different timezone. Hence I want useUTC=true. Now, how do I compute the value (milliseconds) to give to highcharts?

I tried with this python code:

>>> import datetime,time
>>> t=datetime.datetime(2013,11,5,11,30,00)
>>> time.mktime(t.timetuple())*1000
1383647400000.0

But if I plug the value 1383647400000.0 in highcharts I obtain a point with time 10:30 instead of 11:30.

Here is a the code reproducing the malfunctioning: http://jsfiddle.net/2BffA/6/

What am I doing wrong?

Answer 1

The problem was in the python code... The correct way to construct a UTC timestamp for 11:30 november 5, 2013 is

>>> import datetime, calendar
>>> t=datetime.datetime(2013,11,5,11,30,00)
>>> calendar.timegm(t.utctimetuple())*1000.0 + t.microsecond * 0.0011383651000000.0
1383651000000.0

which is the correct timestamp to send to highcharts if useUTC=true