| # File src/library/base/R/ifelse.R |
| # Part of the R package, https://www.R-project.org |
| # |
| # Copyright (C) 1995-2017 The R Core Team |
| # |
| # This program is free software; you can redistribute it and/or modify |
| # it under the terms of the GNU General Public License as published by |
| # the Free Software Foundation; either version 2 of the License, or |
| # (at your option) any later version. |
| # |
| # This program is distributed in the hope that it will be useful, |
| # but WITHOUT ANY WARRANTY; without even the implied warranty of |
| # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| # GNU General Public License for more details. |
| # |
| # A copy of the GNU General Public License is available at |
| # https://www.R-project.org/Licenses/ |
| |
| ifelse <- function (test, yes, no) |
| { |
| if(is.atomic(test)) { # do not lose attributes |
| if (typeof(test) != "logical") |
| storage.mode(test) <- "logical" |
| ## quick return for cases where 'ifelse(a, x, y)' is used |
| ## instead of 'if (a) x else y' |
| if (length(test) == 1 && is.null(attributes(test))) { |
| if (is.na(test)) return(NA) |
| else if (test) { |
| if (length(yes) == 1) { |
| yat <- attributes(yes) |
| if (is.null(yat) || (is.function(yes) && |
| identical(names(yat), "srcref"))) |
| return(yes) |
| } |
| } |
| else if (length(no) == 1) { |
| nat <- attributes(no) |
| if (is.null(nat) || (is.function(no) && |
| identical(names(nat), "srcref"))) |
| return(no) |
| } |
| } |
| } |
| else ## typically a "class"; storage.mode<-() typically fails |
| test <- if(isS4(test)) methods::as(test, "logical") else as.logical(test) |
| ans <- test |
| len <- length(ans) |
| ## which already removes NAs so we don't need to ever call is.na |
| ypos <- which(test) |
| npos <- which(!test) |
| if(length(ypos) > 0L) |
| ans[ypos] <- rep(yes, length.out = len)[ypos] |
| if(length(npos) > 0L) |
| ans[npos] <- rep(no, length.out = len)[npos] |
| ans |
| } |