Godmar, I don't follow...
> q <- list ( ) > q [[ 105 ]] <- as.numeric ( c ( 0 , 0 , 1 ) ) > q [[ 104 ]] <- as.numeric ( c ( 1 , 1 , 1 ) ) > q [[ 10 ]] <- as.integer ( c ( 3 , 3 , 1 ) ) > crossRsorted <- data.frame ( i = c ( 105 , 104 , 10 ) ) > q [ crossRsorted [ , 1 ] ] [[1]] [1] 0 0 1 [[2]] [1] 1 1 1 [[3]] [1] 3 3 1 > length ( q [ crossRsorted [ , 1 ] ] ) [1] 3 > How'd you come up with > length(q) [1] 165 > length(q[ crossRsorted[,1] ]) [1] 15750 I must be missing something. -- David ----------------------------------------------------- David Huffer, Ph.D. Senior Statistician CSOSA/Washington, DC david.huf...@csosa.gov ----------------------------------------------------- -----Original Message----- From: r-help-boun...@r-project.org [mailto:r-help-boun...@r-project.org] On Behalf Of Godmar Back Sent: Wednesday, July 08, 2009 9:58 AM To: Henrique Dallazuanna Cc: r-help@r-project.org; Petr PIKAL Subject: Re: [R] error: no such index at level 2 On Wed, Jul 8, 2009 at 9:40 AM, Henrique Dallazuanna <www...@gmail.com>wrote: > Its because '[[' accept only element, so you need use '[': > > q[crossRsorted[,1]] > This appears to be doing something different. For instance, my 'q' has 165 components, but what you suggest has 15750: > length(q) [1] 165 > length(q[ crossRsorted[,1] ]) [1] 15750 hardly what I want. Meanwhile, it looks as though [[ ]] does not vectorize its arguments, it curries them! Note that: > q[[c(105,104)]] Error in q[[c(105, 104)]] : subscript out of bounds gives the same error as: > q[[105]][[104]] Error in q[[105]][[104]] : subscript out of bounds Very mysterious, though, in all fairness, explained in help("[[") where it says: '[[' can be applied recursively to lists, so that if the single index 'i' is a vector of length 'p', 'alist[[i]]' is equivalent to 'alist[[i1]]...[[ip]]' providing all but the final indexing results in a list. which leads to square one: how to express "select all r[i] where q[[i]] fulfills some predicate?" - Godmar [[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. -----Original Message----- From: r-help-boun...@r-project.org [mailto:r-help-boun...@r-project.org] On Behalf Of Godmar Back Sent: Wednesday, July 08, 2009 9:58 AM To: Henrique Dallazuanna Cc: r-help@r-project.org; Petr PIKAL Subject: Re: [R] error: no such index at level 2 On Wed, Jul 8, 2009 at 9:40 AM, Henrique Dallazuanna <www...@gmail.com>wrote: > Its because '[[' accept only element, so you need use '[': > > q[crossRsorted[,1]] > This appears to be doing something different. For instance, my 'q' has 165 components, but what you suggest has 15750: > length(q) [1] 165 > length(q[ crossRsorted[,1] ]) [1] 15750 hardly what I want. Meanwhile, it looks as though [[ ]] does not vectorize its arguments, it curries them! Note that: > q[[c(105,104)]] Error in q[[c(105, 104)]] : subscript out of bounds gives the same error as: > q[[105]][[104]] Error in q[[105]][[104]] : subscript out of bounds Very mysterious, though, in all fairness, explained in help("[[") where it says: '[[' can be applied recursively to lists, so that if the single index 'i' is a vector of length 'p', 'alist[[i]]' is equivalent to 'alist[[i1]]...[[ip]]' providing all but the final indexing results in a list. which leads to square one: how to express "select all r[i] where q[[i]] fulfills some predicate?" - Godmar [[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.
