You are very lucky. This question was answered last week in https://stat.ethz.ch/pipermail/r-help/2012-October/326597.html
For the future, please read the posting guide referenced below and include an example of your data and the result of the calculation you would like to see. Please use R-help directly and not the nabble interface. On Thu, Oct 25, 2012 at 4:21 PM, pinki751 <raj4technol...@gmail.com> wrote: > hello, > I want to make a two dimensional matrix from the data table.That data > table has three column 1st is userid,2nditemid and 3rd is rating > corresponding to the itemid given by userid.I want to make a m*n matrix in > which 'm' is userid and 'n' to be itemid .That 2D matrix should b filled > with that corresponding rating for that itemid for that userid. please help > me out. > > > > -- > View this message in context: > http://r.789695.n4.nabble.com/List-of-multidimensional-arrays-tp4647286p4647458.html > Sent from the R help mailing list archive at Nabble.com. > > ______________________________________________ > 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. > [[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.