I also tried: > test$Date=as.POSIXct(test$Date,format="%m%d%y") > test=cbind(test,day.of.week=format(test$Date,format="%A")) > head(test) Date Open High Low Close Volume Adj.Close day.of.week 1 <NA> 2.33 2.34 2.31 2.31 5366000 2.31 <NA> 2 <NA> 2.35 2.36 2.33 2.35 5382000 2.35 <NA> 3 <NA> 2.35 2.38 2.34 2.36 9606000 2.36 <NA> 4 <NA> 2.34 2.34 2.30 2.33 9596000 2.33 <NA> 5 <NA> 2.32 2.35 2.31 2.31 5941000 2.31 <NA> 6 <NA> 2.34 2.36 2.32 2.32 10332000 2.32
It didnt help. Thx Raghu On Sun, Apr 22, 2012 at 6:41 PM, Jeff Newmiller <jdnew...@dcn.davis.ca.us>wrote: > On Sun, 22 Apr 2012, Hasan Diwan wrote: > > Raghu, >> >> On 22 April 2012 09:53, Raghuraman Ramachandran <optionsra...@gmail.com >> >wrote: >> >> I have a data frame (from CSV file) which has its first column called >>> Date. >>> The Date is in the format mm/dd/yyyy. I was trying to get the weekday for >>> these dates and I tried using wday() and day.of.week() functions and both >>> of them gave me precisely the wrong answers. I think the issue lies in >>> the >>> proper formatting of dates. The class of this column is a factor class >>> and >>> hence I tried converting into POSIXlt, xts, zoo objects and yet I could >>> not >>> get the weekday correctly. Anyone has any suggestions please? >>> >>> >> Try this: >> # assume dataIn is where the CSV files data is... >> dataIn$Date <- as.POSIXct(dataIn$Date, format='%m/%d/%y') >> > > By far the most common error I see is failing to import the Date column as > character, instead allowing the import function to convert it to factor, > after which computations (such as the above suggestion) use the hidden > factor index instead of the visible character representation, which further > mystifies beginners. The conversion above will only work correctly if the > column was imported as character. E.g. > > dataIn <- read.csv( file="yourdatafile", as.is=TRUE ) > > OP: Use the str() function to see what types you are working with, and in > future R-help queries send dput() of the data and code you have tried if we > are to be able to reproduce your attempts effectively rather than reading > your mind. > > > dataIn <- cbind(dataIn, day.of.week = format(dataIn$Date, format='%A') >> > > Why not just > > dataIn$day.of.week <- weekdays( dataIn$Date ) > > ? > > ------------------------------**------------------------------** > --------------- > Jeff Newmiller The ..... ..... Go Live... > DCN:<jdnew...@dcn.davis.ca.us> Basics: ##.#. ##.#. Live > Go... > Live: OO#.. Dead: OO#.. Playing > Research Engineer (Solar/Batteries O.O#. #.O#. with > /Software/Embedded Controllers) .OO#. .OO#. > rocks...1k > > > ______________________________**________________ > R-help@r-project.org mailing list > https://stat.ethz.ch/mailman/**listinfo/r-help<https://stat.ethz.ch/mailman/listinfo/r-help> > PLEASE do read the posting guide http://www.R-project.org/** > posting-guide.html <http://www.r-project.org/posting-guide.html> > and provide commented, minimal, self-contained, reproducible code. > [[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.
