# File src/library/base/R/sample.R # Part of the R package, http://www.R-project.org # # Copyright (C) 1995-2012 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 # http://www.r-project.org/Licenses/ sample <- function(x, size, replace = FALSE, prob = NULL) { if(length(x) == 1L && is.numeric(x) && x >= 1) { if(missing(size)) size <- x sample.int(x, size, replace, prob) } else { if(missing(size)) size <- length(x) x[sample.int(length(x), size, replace, prob)] } } sample.int <- function(n, size = n, replace = FALSE, prob = NULL) { if (!replace && is.null(prob) && n > 1e7 && size <= n/2) .Internal(sample2(n, size)) else .Internal(sample(n, size, replace, prob)) }