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

只是在上面的答案的基础上,作为安全检查,您可以添加一个包装器,当sys.frame(1)失败时(如果interactive() == TRUE可能会失败),或者源脚本不在主脚本所期望的位置时,它会要求用户找到文件。

fun_path = tryCatch(expr = 
                      {file.path(dirname(sys.frame(1)$ofile), "foo.R")},
                    error = function(e){'foo.R'}
                    )
if(!file.exists(fun_path))
{
  msg = 'Please select "foo.R"'
  # ask user to find data
  if(Sys.info()[['sysname']] == 'Windows'){#choose.files is only available on Windows
    message('\n\n',msg,'\n\n')
    Sys.sleep(0.5)#goes too fast for the user to see the message on some computers
    fun_path  = choose.files(
      default = file.path(gsub('\\\\', '/', Sys.getenv('USERPROFILE')),#user
                          'Documents'),
      caption = msg
    )
  }else{
    message('\n\n',msg,'\n\n')
    Sys.sleep(0.5)#goes too fast for the user to see the message on some computers
    fun_path = file.choose(new=F)
  }
}
#source the function
source(file = fun_path, 
       encoding = 'UTF-8')

我在一个高性能计算集群环境中工作。我在不同的地方开发代码,而不是在生产运行的地方。在开发过程中,我通常从命令行交互式地调用R(而不是使用RStudio)。有很多来源(“foo.R”)正在进行。

在生产运行期间,我通常编写一个bash脚本,尝试不同的参数,并在单独的目录中运行每一组参数。bash脚本利用了工作负载管理器(即SLURM)。在这种环境中,设置环境变量很简单。考虑到这一点,下面的解决方案最适合我。

其他。R

my_message <- function(){
return("R is awkward")
}

foo。R

srcpath = Sys.getenv("R_SRC")
# Check if runnning w/o setting R_SRC - presumably done in directory of development, i.e. /path/to/R/code
if(srcpath == ""){
    srcpath="./"
}
source(sprintf("%s/other.R", srcpath))
string = my_message()
print(string)

如果从R交互式shell中运行,并且在/path/到/R/code中运行,那么简单

> source("foo.R")

如果不是从交互式shell运行,也不是从/path/to/R/code运行,首先设置环境变量R_SRC,然后调用Rscript

$ export R_SRC=/path/to/R/code/
$ Rscript /path/to/R/code/foo.R

你可以在一个bash脚本中包装r脚本,并检索脚本的路径作为bash变量,如下所示:

#!/bin/bash
     # [environment variables can be set here]
     path_to_script=$(dirname $0)

     R --slave<<EOF
        source("$path_to_script/other.R")

     EOF

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))
  }
})()

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(".")