Thanks for clarifying that. Best
Gabor Grothendieck wrote: > > On Wed, Apr 20, 2011 at 5:49 AM, mathijsdevaan > <mathijsdev...@gmail.com> wrote: >> As a follow up on this post, I am trying to slightly adjust the solution >> kindly provided by Gabor. However, I am getting some results that I do >> not >> understand. Example: >> >> # devel version of zoo >> install.packages("zoo", repos = "http://r-forge.r-project.org") >> library(zoo) >> >> DF1 = data.frame(read.table(textConnection(" B C D E F G >> 8025 1995 0 4 1 2 >> 8025 1997 1 1 3 4 >> 8026 1995 0 7 0 0 >> 8026 1996 1 2 3 0 >> 8026 1997 1 2 3 1 >> 8026 1998 6 0 0 4 >> 8026 1999 3 7 0 3 >> 8027 1997 1 2 3 9 >> 8027 1998 1 2 3 1 >> 8027 1999 6 0 0 2 >> 8028 1999 3 7 0 0 >> 8029 1995 0 2 3 3 >> 8029 1998 1 2 3 2 >> 8029 1999 6 0 0 1"),head=TRUE,stringsAsFactors=FALSE)) >> >> a <- read.zoo(DF1, split = 1, index = 2, FUN = identity) >> sum.na <- function(x) if (any(!is.na(x))) sum(x, na.rm = TRUE) else NA >> b <- rollapply(a, 3, sum.na, align = "right", partial = TRUE) >> newDF <- lapply(1:nrow(b), function(i) >> prop.table(na.omit(matrix(b[i,], nc = 4, byrow = TRUE, >> dimnames = list(unique(DF1$B), names(DF1)[-1:-2]))), 1)) >> names(newDF) <- time(a) >> c<-lapply(newDF, function(mat) tcrossprod(mat / sqrt(rowSums(mat^2)))) >> >> Now I would like the elements e in c to be equal to 1-e. However, >> >> c<-lapply(newDF, function(mat) 1 - tcrossprod(mat / >> sqrt(rowSums(mat^2)))) >> >> gives a value of 2.220446e-16 for as.data.frame(c['1999'])[2,2] instead >> of >> 0 >> >> What am I doing wrong here? Thanks a lot! >> > > See FAQ 7.31 at: > > http://cran.r-project.org/doc/FAQ/R-FAQ.html#Why-doesn_0027t-R-think-these-numbers-are-equal_003f > > > -- > Statistics & Software Consulting > GKX Group, GKX Associates Inc. > tel: 1-877-GKX-GROUP > email: ggrothendieck at gmail.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. > -- View this message in context: http://r.789695.n4.nabble.com/Yearly-aggregates-and-matrices-tp3438140p3463000.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.