我有一个名为foo的脚本。R包含另一个脚本other。R,在同一个目录下:

#!/usr/bin/env Rscript
message("Hello")
source("other.R")

但我想让R找到另一个。R,不管当前工作目录是什么。

换句话说,就是foo。R需要知道自己的路径。我该怎么做呢?


当前回答

当从R控制台“来源”时,我无法得到Suppressingfire的解决方案。 当使用Rscript时,我无法得到hadley的解决方案。

两全其美?

thisFile <- function() {
        cmdArgs <- commandArgs(trailingOnly = FALSE)
        needle <- "--file="
        match <- grep(needle, cmdArgs)
        if (length(match) > 0) {
                # Rscript
                return(normalizePath(sub(needle, "", cmdArgs[match])))
        } else {
                # 'source'd via R console
                return(normalizePath(sys.frames()[[1]]$ofile))
        }
}

其他回答

这个问题有一个简单的解决办法。这个命令:

script.dir <- dirname(sys.frame(1)$ofile)

返回当前脚本文件的路径。它在保存脚本后工作。

I would use a variant of @steamer25 's approach. The point is that I prefer to obtain the last sourced script even when my session was started through Rscript. The following snippet, when included on a file, will provided a variable thisScript containing the normalized path of the script. I confess the (ab)use of source'ing, so sometimes I invoke Rscript and the script provided in the --file argument sources another script that sources another one... Someday I will invest in making my messy code turns into a package.

thisScript <- (function() {
  lastScriptSourced <- tail(unlist(lapply(sys.frames(), function(env) env$ofile)), 1)

  if (is.null(lastScriptSourced)) {
    # No script sourced, checking invocation through Rscript
    cmdArgs <- commandArgs(trailingOnly = FALSE)
    needle <- "--file="
    match <- grep(needle, cmdArgs)
    if (length(match) > 0) {
      return(normalizePath(sub(needle, "", cmdArgs[match]), winslash=.Platform$file.sep, mustWork=TRUE))
    }
  } else {
    # 'source'd via R console
    return(normalizePath(lastScriptSourced, winslash=.Platform$file.sep, mustWork=TRUE))
  }
})()

当从R控制台“来源”时,我无法得到Suppressingfire的解决方案。 当使用Rscript时,我无法得到hadley的解决方案。

两全其美?

thisFile <- function() {
        cmdArgs <- commandArgs(trailingOnly = FALSE)
        needle <- "--file="
        match <- grep(needle, cmdArgs)
        if (length(match) > 0) {
                # Rscript
                return(normalizePath(sub(needle, "", cmdArgs[match])))
        } else {
                # 'source'd via R console
                return(normalizePath(sys.frames()[[1]]$ofile))
        }
}

Steamer25的方法是有效的,但前提是路径中没有空白。在macOS上,至少cmdArgs[match]返回类似/base/some~+~dir~+~带~+~空格/ for /base/some\ dir\带\空格/。

我通过在返回之前用一个简单的空格替换“~+~”来解决这个问题。

thisFile <- function() {
  cmdArgs <- commandArgs(trailingOnly = FALSE)
  needle <- "--file="
  match <- grep(needle, cmdArgs)
  if (length(match) > 0) {
    # Rscript
    path <- cmdArgs[match]
    path <- gsub("\\~\\+\\~", " ", path)
    return(normalizePath(sub(needle, "", path)))
  } else {
    # 'source'd via R console
    return(normalizePath(sys.frames()[[1]]$ofile))
  }
}

显然,你仍然可以像aprstar那样扩展else块。

这对我很有用。只是从命令行参数中greps它,去掉不需要的文本,执行dirname,最后从它获得完整的路径:

args <- commandArgs(trailingOnly = F)  
scriptPath <- normalizePath(dirname(sub("^--file=", "", args[grep("^--file=", args)])))