Hi, Just to add: Infact, there is a small difference in both the approaches. For e.g when tested with your data sapply(l,`[`,1:4) # [,1] [,2] [,3] [,4] [,5] #[1,] 1.0 3 4 2 3 #[2,] 2.0 4 2 4 5 #[3,] 3.7 5 5 6 7 #[4,] NA 6 7 3 2 sapply(l,head,4) #[[1]] #[1] 1.0 2.0 3.7 # #[[2]] #[1] 3 4 5 6 # #[[3]] #[1] 4 2 5 7 # #[[4]] #[1] 2 4 6 3 # #[[5]] #[1] 3 5 7 2 sapply(sapply(l,head,4),`[`,1:4) # [,1] [,2] [,3] [,4] [,5] #[1,] 1.0 3 4 2 3 #[2,] 2.0 4 2 4 5 #[3,] 3.7 5 5 6 7 #[4,] NA 6 7 3 2 A.K.
----- Original Message ----- From: Al Ehan <aehan3...@gmail.com> To: r-help@r-project.org Cc: Sent: Thursday, November 1, 2012 4:11 AM Subject: [R] convert list without same component length to matrix 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. ______________________________________________ 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.
