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
Supressingfire回答的简化版本:
source_local <- function(fname){
argv <- commandArgs(trailingOnly = FALSE)
base_dir <- dirname(substring(argv[grep("--file=", argv)], 8))
source(paste(base_dir, fname, sep="/"))
}
其他回答
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]]$ofile))
}
}
I would use a variant of @steamer25 's approach. The point is that I prefer to obtain the last sourced script even when my session was started through Rscript. The following snippet, when included on a file, will provided a variable thisScript containing the normalized path of the script. I confess the (ab)use of source'ing, so sometimes I invoke Rscript and the script provided in the --file argument sources another script that sources another one... Someday I will invest in making my messy code turns into a package.
thisScript <- (function() {
lastScriptSourced <- tail(unlist(lapply(sys.frames(), function(env) env$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))
}
})()
我对上面的实现有问题，因为我的脚本是从符号链接目录操作的，或者至少这就是为什么我认为上面的解决方案不适合我。按照@ennuikiller的回答，我将Rscript包装在bash中。我使用pwd -P设置路径变量，它解析符号链接目录结构。然后将路径传递给Rscript。
Bash.sh
#!/bin/bash
# set path variable
path=`pwd -P`
#Run Rscript with path argument
Rscript foo.R $path
foo。R
args <- commandArgs(trailingOnly=TRUE)
setwd(args[1])
source(other.R)
我喜欢这种方法:
this.file <- sys.frame(tail(grep('source',sys.calls()),n=1))$ofile
this.dir <- dirname(this.file)
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。
