| # File src/library/graphics/R/identify.R |
| # Part of the R package, https://www.R-project.org |
| # |
| # Copyright (C) 1995-2016 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/ |
| |
| identify <- function(x, ...) UseMethod("identify") |
| |
| identify.default <- |
| function(x, y = NULL, labels = seq_along(x), pos = FALSE, |
| n = length(x), plot = TRUE, atpen = FALSE, |
| offset = 0.5, tolerance = 0.25, order = FALSE, ...) |
| { |
| if(length(extras <- list(...))) { |
| opar <- par(extras) |
| on.exit(par(opar)) |
| } |
| xy <- xy.coords(x, y, setLab = FALSE) |
| x <- xy$x |
| y <- xy$y |
| if (length(x) == 0) { |
| if (!pos && !order) |
| return(numeric()) |
| else { |
| result <- list(ind = numeric()) |
| if (pos) |
| result$pos <- numeric() |
| if (order) |
| result$order <- numeric() |
| return(result) |
| } |
| } |
| z <- .External2(C_identify, x, y, as.character(labels), n, plot, |
| offset, tolerance, atpen) |
| i <- seq.int(z[[1L]])[z[[1L]]] |
| if (!pos && !order) |
| i |
| else { |
| result <- list(ind = i) |
| if (pos) |
| result$pos <- z[[2L]][z[[1L]]] |
| if (order) |
| result$order <- z[[3L]][z[[1L]]] |
| result |
| } |
| } |