Have a look at the "lubridate" package. It claims to try to make dealing with dates easier.
-- Bert On Fri, Nov 8, 2013 at 11:41 AM, Alemu Tadesse <alemu.tade...@gmail.com> wrote: > Dear All, > > I usually work with time series data. The data may come in AM/PM date > format or on 24 hour time basis. R can not recognize the two differences > automatically - at least for me. I have to specifically tell R in which > time format the data is. It seems that Pandas knows how to handle date > without being told the format. The problem arises when I try to shift time > by a certain time. Say adding 3600 to shift it forward, that case I have to > use something like: > Measured_data$Date <- as.POSIXct(as.character(Measured_data$Date), > tz="",format = "%m/%d/%Y %I:%M %p")+3600 > or Measured_data$Date <- as.POSIXct(as.character(Measured_data$Date), > tz="",format = "%m/%d/%Y %H:%M")+3600 depending on the format. The date > also attaches MDT or MST and so on. When merging two data frames with > dates of different format that may create a problem (I think). When I get > data from excel it could be in any/random format and I needed to customize > the date to use in R in one of the above formats. Any TIPS - for automatic > processing with no need to specifically tell the data format ? > > Another problem I saw was that when using r bind to bind data frames, if > one column of one of the data frames is a character data (say for example > none - coming from mysql) format R doesn't know how to concatenate numeric > column from the other data frame to it. I needed to change the numeric to > character and later after binding takes place I had to re-convert it to > numeric. But, this causes problem in an automated environment. Any > suggestion ? > > Thanks > Mihretu > > [[alternative HTML version deleted]] > > ______________________________________________ > R-help@r-project.org 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. -- Bert Gunter Genentech Nonclinical Biostatistics (650) 467-7374 ______________________________________________ R-help@r-project.org 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.
