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

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))
  }
})()

其他回答

你可以使用commandArgs函数获取Rscript传递给实际R解释器的所有选项,并搜索——file=。如果你的脚本是从路径启动的,或者它是以一个完整的路径启动的,下面的script.name将以'/'开头。否则,它必须是相对于cwd,你可以连接两个路径,以获得完整的路径。

编辑:听起来你只需要上面的script.name,并剥离路径的最后一个组件。我已经删除了不需要的cwd()样本,并清理了主脚本,并张贴了我的其他. r。只需要保存这个脚本和其他脚本。R脚本放到同一个目录下,chmod +x它们,然后运行主脚本。

主要。接待员:

#!/usr/bin/env Rscript
initial.options <- commandArgs(trailingOnly = FALSE)
file.arg.name <- "--file="
script.name <- sub(file.arg.name, "", initial.options[grep(file.arg.name, initial.options)])
script.basename <- dirname(script.name)
other.name <- file.path(script.basename, "other.R")
print(paste("Sourcing",other.name,"from",script.name))
source(other.name)

其他。接待员:

print("hello")

输出:

burner@firefighter:~$ main.R
[1] "Sourcing /home/burner/bin/other.R from /home/burner/bin/main.R"
[1] "hello"
burner@firefighter:~$ bin/main.R
[1] "Sourcing bin/other.R from bin/main.R"
[1] "hello"
burner@firefighter:~$ cd bin
burner@firefighter:~/bin$ main.R
[1] "Sourcing ./other.R from ./main.R"
[1] "hello"

我相信这就是德曼在找的东西。

我已经将这个问题的答案打包并扩展为rprojroot中的新函数thisfile()。也适用于编织与针织。

99%的情况你可以简单地使用:

sys.calls()[[1]] [[2]]

它将不适用于脚本不是第一个参数的疯狂调用,即source(some args, file="myscript")。在这些奇特的情况下使用@hadley's。

我自己刚算出来的。为了确保脚本的可移植性,总是以以下开头:

wd <- setwd(".")
setwd(wd)

It works because "." translates like the Unix command $PWD. Assigning this string to a character object allows you to then insert that character object into setwd() and Presto your code will always run with its current directory as the working directory, no matter whose machine it is on or where in the file structure it is located. (Extra bonus: The wd object can be used with file.path() (ie. file.path(wd, "output_directory") to allow for the creation of a standard output directory regardless of the file path leading to your named directory. This does require you to make the new directory before referencing it this way but that, too, can be aided with the wd object.

或者,下面的代码执行完全相同的事情:

wd <- getwd()
setwd(wd)

或者,如果你不需要对象中的文件路径,你可以简单地:

setwd(".")

参见R.utils包的findSourceTraceback(),其中

查找source()在所有调用帧中生成的所有'srcfile'对象。 这使得可以找出当前由source()编写脚本的文件。