Hi Bogdan, Does the following do what you expect?
x$intersectA[[i]] <- c(x$intersectA[[i]], x$labA[j]) Note the difference between `[[` and `[` On Wed, Jul 25, 2018 at 9:26 AM, Bogdan Tanasa <tan...@gmail.com> wrote: > Dear Thierry and Juan, thank you for your help. Thank you very much. > > Now, if I would like to add an element to the empty list, how shall I do : > for example, shall i = 2, and j = 1, in a bit of more complex R code : > > x <- data.frame(TYPE=c("DEL", "DEL", "DUP", "TRA", "INV", "TRA"), > CHRA=c("chr1", "chr1", "chr1", "chr1", "chr2", "chr2"), > POSA=c(10, 15, 120, 340, 100, 220), > CHRB=c("chr1", "chr1", "chr1", "chr2", "chr2", "chr1"), > POSB=c(30, 100, 300, 20, 200, 320)) > > x$labA <- paste(x$CHRA, x$POSA, sep="_") > x$labB <- paste(x$CHRB, x$POSB, sep="_") > > x$POSA_left <- x$POSA - 10 > x$POSA_right <- x$POSA + 10 > > x$POSB_left <- x$POSB - 10 > x$POSB_right <- x$POSB + 10 > > x$intersectA <- rep(list(list()), nrow(x)) > x$intersectB <- rep(list(list()), nrow(x)) > > And we know that for i = 2, and j = 1, the condition is TRUE : > > i <- 2 > j <- 1 > > if ( (x$CHRA[i] == x$CHRA[j] ) && > (x$POSA[i] > x$POSA_left[j] ) && > (x$POSA[i] < x$POSA_right[j] ) ) > { > x$intersectA[i] <- c(x$intersectA[i], x$labA[j]) > } > > the R code does not work. Thank you for your kind help ! > > >> >> On Wed, Jul 25, 2018 at 12:26 AM, Thierry Onkelinx < >> thierry.onkel...@inbo.be> wrote: >> >>> Dear Bogdan, >>> >>> You are looking for x$intersectA <- vector("list", nrow(x)) >>> >>> Best regards, >>> >>> >>> ir. Thierry Onkelinx >>> Statisticus / Statistician >>> >>> Vlaamse Overheid / Government of Flanders >>> INSTITUUT VOOR NATUUR- EN BOSONDERZOEK / RESEARCH INSTITUTE FOR NATURE >>> AND FOREST >>> Team Biometrie & Kwaliteitszorg / Team Biometrics & Quality Assurance >>> thierry.onkel...@inbo.be >>> Havenlaan 88 >>> <https://maps.google.com/?q=Havenlaan+88&entry=gmail&source=g> bus 73, >>> 1000 Brussel >>> www.inbo.be >>> >>> //////////////////////////////////////////////////////////// >>> /////////////////////////////// >>> To call in the statistician after the experiment is done may be no more >>> than asking him to perform a post-mortem examination: he may be able to say >>> what the experiment died of. ~ Sir Ronald Aylmer Fisher >>> The plural of anecdote is not data. ~ Roger Brinner >>> The combination of some data and an aching desire for an answer does not >>> ensure that a reasonable answer can be extracted from a given body of data. >>> ~ John Tukey >>> //////////////////////////////////////////////////////////// >>> /////////////////////////////// >>> >>> <https://www.inbo.be> >>> >>> 2018-07-25 8:55 GMT+02:00 Bogdan Tanasa <tan...@gmail.com>: >>> >>>> Dear all, >>>> >>>> assuming that I do have a dataframe like : >>>> >>>> x <- data.frame(TYPE=c("DEL", "DEL", "DUP", "TRA", "INV", "TRA"), >>>> CHRA=c("chr1", "chr1", "chr1", "chr1", "chr2", "chr2"), >>>> POSA=c(10, 15, 120, 340, 100, 220), >>>> CHRB=c("chr1", "chr1", "chr1", "chr2", "chr2", "chr1"), >>>> POSB=c(30, 100, 300, 20, 200, 320)) , >>>> >>>> how could I initiate another 2 columns in x, where each element in these >>>> 2 >>>> columns is going to be a list (the list could be updated later). Thank >>>> you ! >>>> >>>> Shall I do, >>>> >>>> for (i in 1:dim(x)[1]) { x$intersectA[i] <- list()} >>>> >>>> for (i in 1:dim(x)[1]) { x$intersectB[i] <- list()} >>>> >>>> nothing is happening. Thank you very much ! >>>> >>>> [[alternative HTML version deleted]] >>>> >>>> ______________________________________________ >>>> R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see >>>> https://stat.ethz.ch/mailman/listinfo/r-help >>>> PLEASE do read the posting guide http://www.R-project.org/posti >>>> ng-guide.html >>>> and provide commented, minimal, self-contained, reproducible code. >>>> >>> >>> >> > > [[alternative HTML version deleted]] > > ______________________________________________ > R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see > 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 -- To UNSUBSCRIBE and more, see 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.