I frequently work with hourly data in GMT format, and ensure that any data I read into R are expressed in GMT through as.POSIXct(mydate, tz = "GMT").
I am interested in processing air pollution data in GMT where where peaks in emissions (say from road traffic sources) tend to occur at the same LOCAL time each day. I am interested in calculating mean concentrations by hour of day i.e. a diurnal profile, consisting of 24 hourly means. The profile would be clearer if all hours were in local time e.g. the daylight saving hours were shifted by +1 hour. This would ensure that the summer and winter profiles match up with those in emissions. I've looked though the various R documents/forum, but can't seem to identify the easiest approach to this. Any suggestions? Many thanks. David -- View this message in context: http://www.nabble.com/time-zone---best-way-to-shift-hours-tp18627900p18627900.html Sent from the R help mailing list archive at Nabble.com. [[alternative HTML version deleted]] ______________________________________________ [email protected] mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
