Dear R-help, I was trying to convert a date and time record extracted from a fortran subroutine I worte and I encounter some problem. The data read in time and date in a format like "2000-05-11_01:00:00.0000" in fortran output. It is in GMT. I need to convert it to CST (GMT+8). I did the following steps. > cdate [1] "2000-05-11_01:00:00.0000\005\003" # I am not sure why the extra characters at the end but it doesn't affect the strptime function so I just ingored it. > strptime(cdate,format="%Y-%m-%d_%H:%M:%S") [1] "2000-05-11 01:00:00" # In order to incoporate GMT into the record, I use paste function to stick it in. >as.POSIXct(as.character(strptime(cdate,format="%Y-%m-%d_%H:%M:%S")),tz="GMT") [1] "2000-05-11 01:00:00 GMT" #It is easier to just do a arthmatic to convert the timezone and ingore this attribute like > as.POSIXct(as.character(strptime(cdate,format="%Y-%m-%d_%H:%M:%S")),tz="CST")+(8*3600) [1] "2000-05-11 09:00:00 CST" I was wondering if there is a simpler method to do this. Thanks in advance, Simon