Thanks. I suddenly realised this as I was cycling down to the local grocery store, about 10 minutes after posting the problem. I felt like an idiot. Thanks for confirming my stupidity.
john --- On Sat, 2/26/11, Phil Spector <spec...@stat.berkeley.edu> wrote: > From: Phil Spector <spec...@stat.berkeley.edu> > Subject: Re: [R] Transform a dataset from long to wide using reshape2 > To: "John Kane" <jrkrid...@yahoo.ca> > Cc: "R R-help" <r-h...@stat.math.ethz.ch> > Received: Saturday, February 26, 2011, 2:24 PM > John - > In the dat data frame, there is exactly one > observation > for each Subject/Item combination, so it's clear how to > rearrange the values of Score. In the mydata data > frame there > are multiple values for most combinations of x and id, so > reshape2 needs to aggregate y before it can rearrange the > values. > Hope this helps. > > - Phil Spector > > Statistical > Computing Facility > > Department > of Statistics > > UC > Berkeley > > spec...@stat.berkeley.edu > > > > On Sat, 26 Feb 2011, John Kane wrote: > > > I seem to be running into the same problem reported > in > > https://stat.ethz.ch/pipermail/r-help/2010-November/258265.html > > > > I cannot seem to transform a dataset from long to wide > using reshape2. > > Clearly I am missing something very simple but a look > at the manual and the reshape paper in JSS does not suggest > anything. > > > > Any advice would be welcome > > ===========================load > rehape2==================== > > library(reshape2) > > ========================Working > example=========================== > > # Example from above URL > > dat <- > read.table(textConnection('Subject Item > Score > > "Subject 1" "Item 1" 1 > > "Subject 1" "Item 2" 0 > > "Subject 1" "Item 3" 1 > > "Subject 2" "Item 1" 1 > > "Subject 2" "Item 2" 1 > > "Subject 2" "Item 3" 0'), > header=TRUE) > > closeAllConnections() > > > > acast(dat, Subject~Item) > > > > # Seems fine > > =====================My > attemp=========================== > > # > > set.seed(1) > > mydata <- data.frame( x=sample(LETTERS[23:26],100, > replace=TRUE), > > y=rnorm(100, mean=2), > id=sample(letters[1:4], 100, replace=TRUE)) > > > > acast(mydata , id ~ x) > > # not so fine > > > ================================================================= > > produces this : > > Using id as value column: use value_var to override. > > Aggregation function missing: defaulting to length > > W X Y Z > > a 7 5 5 7 > > b 6 9 6 12 > > c 1 4 5 6 > > d 6 14 5 2 > > > > Why does reshape2 think it needs an aggregation > function here> > > > > Thanks > > > > ______________________________________________ > > 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. > > > ______________________________________________ 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.