try this: l <- list(c(1,2,3,7), c(3,4,5,6,3), c(4,2,5,7), c(2,4,6,3,2), c(3,5,7,2))
sapply(l, head, 4) I hope it helps. Best, Dimitris On 11/1/2012 9:11 AM, Al Ehan wrote: > Hi, > > I have this lame question. I want to convert a list (each with varies in > length) to matrix with same row length by eliminating vectors outside the > needed range. > For example: > > l<-list(NULL) > l[[1]]=1,2,3.7 > l[[2]]=3,4,5,6,3 > l[[3]]=4,2,5,7 > l[[4]]=2,4,6,3,2 > l[[5]]=3,5,7,2 > > > #so say I want to only have 4 rows and 5 column in my matrix (or > data.frame) and eliminating the 5th index value in l[[2]] and l[[4]] > #what is the simplest code would be? I actually have hundreds of the list > components. > > thanks > > [[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. > -- Dimitris Rizopoulos Assistant Professor Department of Biostatistics Erasmus University Medical Center Address: PO Box 2040, 3000 CA Rotterdam, the Netherlands Tel: +31/(0)10/7043478 Fax: +31/(0)10/7043014 Web: http://www.erasmusmc.nl/biostatistiek/ ______________________________________________ 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.