How does R's built-in system() function know where to look to invoke some arbitrary OS command specified by the command argument? For example, if I homebrew install some_command_line_program, how does R's system() function know where it is located when I type:
cmd <- "some_complicated_code_from_some_command_line_program"
system(cmd, wait=FALSE)
In other words, how is R smart enough to know where to look without any user input? If I compile from source via Github (instead of homebrew install), would system() also recognize the command?
What system does depends on your OS, you've not told us (although you've given us some clues...).
On unix-alike systems, it executes it as a command in a bash shell, which searches for the first match in the directories on the $PATH environment variable. You can see what that is in R:
> Sys.getenv("PATH")
[1] "/usr/local/heroku/bin:/usr/local/heroku/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/nobackup/rowlings/NEST4B"
In Windows, it does something else.
You can get a full path to whatever it might run with Sys.which, which uses the systems' which command on unixes and fakes it on Windows. Read the help for more.
If you compile something from source then it will be found if the file that runs the command (a shell script, an executable, a #!-script in any language) is placed in a folder in your $PATH. You can create a folder yourself, say /home/user/bin, put your executables in there, add that to your $PATH, and (possibly after logging out an in again, or restarting R, or just firing up a new shell...) then R will find it.
Related
shell_exec("Rscript C:\R\R-3.2.2\bin\code.R ");
This is the call to script.On calling the above script, the error occurs.
I am trying to call my R script from the above path but no output is being shown. While checking the error logs of PHP, it says 'Rscript' is not recognized as an internal or external command, operable program or batch file.' The script is working fine on the Rstudio but not running on the command line.
Add the Rscript path to your environment variables in Windows:
Go to Control Panel\System and Security\System and click Advanced System Settings, then environment variables, click on path in the lower box, edit, add "C:\R\R-3.2.2\bin"
Restart everything. Should be good to go. Then you should be able to do
exec('Rscript PATH/TO/my_code.R')
instead of typing the full path to Rscript. Won't need the path to your my_code.R script if your php file is in the same directory.
You need to set the proper path where your RScript.exe program is located.
exec ("\"C:\\R\\R-3.2.2\\bin\\Rscript.exe\"
C:\\My_work\\R_scripts\\my_code.R my_args";
#my_args only needed if you script take `args`as input to run
other way is you declare header in your r script (my_code.r)
#!/usr/bin/Rscript
and call it from command line
./my_code.r
If you are running it in Git Bash terminal, you could follow a revised version of the idea suggested by #user5249203: in the first line of your file my_code.R, type the following
#!/c/R/R-3.2.2/bin/Rscript.exe
I assumed that your path to Rscript.exe is the one listed above C:\R\R-3.2.2\bin. For anyone having a different path to Rscript.exe in Windows, just modify the path-to-Rscript accordingly. After this modification of your R code, you could run it in the Git Bash terminal using path-to-the-code/mycode.R. I have tested it on my pc.
I faced the same problem while using r the first time in VS Code, just after installing the language package (CRAN).
I restart the application and everything worked perfectly. I think restarting would work for you as well.
In R packages there can be a directory exec which contains some executable scripts. I have such a script called json_merge.R in my package numericprojection. This gets installed to ~/R/x86_64-redhat-linux-gnu-library/3.6/numericprojection/exec/json_merge.R.
To execute it I can of course specify that particular path and call it with Rscript from the command line. I was wondering whether there is some way to have R resolve this path such that I could just specify json_merge.R and numericprojection.
In the meantime I constructed this here:
r_libs_user="$(Rscript -e "cat(Sys.getenv('R_LIBS_USER'))")"
script="$r_libs_user/numericprojection/exec/projected_merge.R"
script="${script/#\~/$HOME}" # https://stackoverflow.com/a/27485157/653152
"$script"
That's what the system.file command is for. In your case that command should look like this:
system.file("exec", "json_merge.R", package = "numericprojection")
And will return:
~/R/x86_64-redhat-linux-gnu-library/3.6/numericprojection/exec/json_merge.R
If that is where the file was installed.
However, I think that your question is likely based on a misunderstanding as outlined in the comments.
Hej,
When I try to call QIIME with a system call from R, i.e
system2("macqiime")
R stops responding. It's no problem with other command line programs though.
can certain programs not be called from R via system2() ?
MacQIIME version:
MacQIIME 1.8.0-20140103
Sourcing MacQIIME environment variables...
This is the same as a normal terminal shell, except your default
python is DIFFERENT (/macqiime/bin/python) and there are other new
QIIME-related things in your PATH.
(note that I am primarily interested to call QIIME from R Markdown with engine = "sh" which fails, too. But I strongly suspect the problems are related)
In my experience, when you call Qiime from unix command line, it usually creates a virtual shell of it`s own to run its commands which is different from regular system commands like ls or mv. I suspect you may not be able to run Qiime from within R unless you emulate that same shell or configuration Qiime requires. I tried to run it from a python script and was not successful.
How am i able to execute UNIX commands on my PC Command prompt? Note i do not have cygwin installed, although i was going to before i discovered this.
This is a development machine so i have a lot installed on it like ruby, python, git, github, node and so on.
What does this mean? can i use this without cygwin?
Here is a list of programs installed on my PC program list
How am I able to execute UNIX commands on my PC Command prompt?
You can use the where command in a cmd shell to find out the exact location of your Unix commands, for example:
where ls
This assumes, of course, that ls is located somewhere in your current PATH.
The location returned will show you in which directory your Unix commands are installed and may be enough for you to determine how they were installed.
The where command is roughly equivalent to the Unix which command.
By default, the search is done in the current directory and in the
PATH.
Syntax
WHERE [/r Dir] [/q] [/f] [/t] Pattern ...
WHERE [/q] [/f] [/t] [$ENV:Pattern
Source where
Further Reading
An A-Z Index of the Windows CMD command line - An excellent reference for all things Windows cmd line related.
where - Locate and display files in a directory tree.
Running Unix commands in windows can be done by having a tool like Cygwin which has those commands.
You can also get many of those commands compiled for windows and then run them using the command with the full path or only the command if the executable is in a path known by adding the paths to the executable files in Windows by :
1) Running in the terminal: PATH %PATH%;C:\<new_path>
2) Creating command aliases like: doskey np=C:\<new_path>\new_command.exe $*. $* is used to be able to transmit parameters
I want to run R files in batch mode using Rscript, however it does not seem to be loading the libraries that I need. The specific error I am getting is:
Error in library(timeSeries) : there is no package called 'timeSeries'
Execution halted
However I do have the package timeSeries and can load it from Rstudio, RGui, and R from the command line no problem. The issue seems to only be when running a script using Rscript.
My system/environment variables are configured as:
C:\Program Files\R\R-3.1.0\bin\x64 (Appended to PATH)
R_HOME = C:\Program Files\R\R-3.1.0
R_User = Patrick
I am running the same version of R in RStudio, RGui, and R from command line. I've also checked .Library from these three sources and got the same output as well.
How can I run Rscript from command line with the packages that I am using (and have installed) in R?
EDIT:
I am using Rscript via Rscript script.r at the windows command line in the directory where script.r is located.
The output of Rscript -e print(.Library) is [1] "C:/PROGRA~1/R/R-31~1.0/library"
which is consistent with the other three options that I mentioned: [1] "C:/PROGRA~1/R/R-31~1.0/library"
However, if I put this in my script:
print(.libPaths())
library(timeSeries) #This is the package that failed to load
I get an output of:
[1] "C:/Program Files/R/R-3.1.0/library"
Error in library(timeSeries) : there is no package called 'timeSeries'
Execution halted
The corresponding call in RStudio gives an additional path to where the package is actually installed:
> print(.libPaths())
[1] "C:/Users/Patrick/Documents/R/win-library/3.1" "C:/Program Files/R/R-3.1.0/library"
In short, the value returned by calling Sys.getenv('R_LIBS_USER') in R.exe needs to be the same as the value returned by calling this at the command line:
Rscript.exe -e "Sys.getenv('R_LIBS_USER')"
and the above value needs to be included in this command line call:
Rscript.exe -e ".libPaths()"
Note that the values of R_LIBS_USER may be differ between R.exe and Rscript.exe if the value of R_USER is changed, either in the .Rprofile or the in target field of user's shortcut to R.exe, and in general, I find that the user library (i.e. .libPaths()[2]) is simply not set in Rscript.exe
Since I'm fond of setting R_USER to my USERPROFILE, I include the following block in at the top of .R files that I wish to run on mulitiple computers or in Rscript.exe's .Rprofile (i.e. Rscript -e "path.expand('~/.Rprofile')"):
# =====================================================================
# For compatibility with Rscript.exe:
# =====================================================================
if(length(.libPaths()) == 1){
# We're in Rscript.exe
possible_lib_paths <- file.path(Sys.getenv(c('USERPROFILE','R_USER')),
"R","win-library",
paste(R.version$major,
substr(R.version$minor,1,1),
sep='.'))
indx <- which(file.exists(possible_lib_paths))
if(length(indx)){
.libPaths(possible_lib_paths[indx[1]])
}
# CLEAN UP
rm(indx,possible_lib_paths)
}
# =====================================================================
As mentioned in the comments, it seems Rscript doesn't recognize the library path defaults automatically. I am writing an R script that needs to be source-able from the command line on different people's computers, so I came up with this more general workaround:
First store the default library path in a variable (Rscript-sourced functions can find this, they just don't automatiocally)
Then include that path in the library() call with lib.loc = argument.
This should work regardless of what the path is on a given computer.
library.path <- .libPaths()
library("timeseries", lib.loc = library.path)
Thanks again to #flodel above for putting me on the right path
This answer will not help the original asker (pbreach), but it may help someone else who stumbles across this question and has a similar problem to me.
I have many bash .sh script files which call RScript to execute .R files. My operating system is Windows 10, and I execute those bash files using cygwin.
Everything had been working fine until yesterday, when I finally upgraded my R from Revolution R 8.0.1 beta to Microsoft R Open 3.4.1. After that upgrade, every bash script that called RScript failed due to the exact same reason asked here (e.g. Error in library(zoo) : there is no package called 'zoo').
Investigation revealed that RScript actually worked fine if called from a DOS shell instead of from a cygwin bash shell.
For example, if I execute this in a DOS shell
C:\Progra~1\Microsoft\ROpen~1\R-3.4.1\bin\x64\Rscript.exe -e ".libPaths()"
I see the output
[1] "C:/Users/HaroldFinch/Documents/R/win-library/3.4"
[2] "C:/Program Files/Microsoft/R Open/R-3.4.1/library"
I eventually discovered the reason. As explained in the R FAQ, to define its home directory, R will first use the R_USER environment variable if defined, else it will use HOME environment variable if defined, else it will use the Windows "personal" directory.
My Windows configuration does not define either R_USER or HOME environment variables. So, in the DOS shell case, R uses my Windows "personal" directory (C:/Users/HaroldFinch/Documents). That is good, because that is where all my libraries are installed (C:/Users/HaroldFinch/Documents/R/win-library/3.4).
In contrast, cygwin defines and exports a HOME environment variable that points to my cygwin user directory, which lacks any R stuff. Hence, RScript called from cygwin had a wrong R home directory, and so failed to load libraries.
There are probably many ways to solve this. I decided to have my bash script set a R_USER environment variable which points to my Windows user directory.
For example, if I execute this in a cygwin bash shell:
R_USER="C:/Users/HaroldFinch/Documents"
export R_USER
/cygdrive/c/Progra~1/Microsoft/ROpen~1/R-3.4.1/bin/x64/Rscript.exe -e ".libPaths()"
I see the output
[1] "C:/Users/HaroldFinch/Documents/R/win-library/3.4"
[2] "C:/Program Files/Microsoft/R Open/R-3.4.1/library"
which is exactly the same output now as the DOS shell example above.
Another cause is packrat. If you are running with packrat, RStudio turns it on for you when you open the project. RScript does not, so you need a packrat::on() early in your script (before the library calls).
As the others have already pointed out, the problem is that Rscript.exe cannot recognise the win-library folder. The easiest solution for me was to explicitly set the path to the library folder by adding:
.libPaths("C:/Users/Benutzer1/Documents/R/win-library/4.0")
to my program. Then it loads all the packages from the win-library folder and it is still capable of loading packages from the standard library folder.