I am writing an R code on a Linux system using RStudio. At some point in the code, I need to use a system call to a command that will download a few thousand of files from the lines of a text file:
down.command <- paste0("parallel --gnu -a links.txt wget")
system(down.command)
However, this command takes a little while to run (a couple of hours), and the R prompt stays locked while the command runs. I would like to keep using R while the command runs on the background.
I tried to use nohup like this:
down.command <- paste0("nohup parallel --gnu -a links.txt wget > ~/down.log 2>&1")
system(down.command)
but the R prompt still gets "locked" waiting for the end of the command.
Is there any way to circumvent this? Is there a way to submit system commands from R and keep them running on the background?
Using ‘processx’, here’s how to create a new process that redirects both stdout and stderr to the same file:
args = c('--gnu', '-a', 'links.txt', 'wget')
p = processx::process$new('parallel', args, stdout = '~/down.log', stderr = '2>&1')
This launches the process and resumes the execution of the R script. You can then interact with the running process via the p name. Notably you can signal to it, you can query its status (e.g. is_alive()), and you can synchronously wait for its completion (optionally with a timeout after which to kill it):
p$wait()
result = p$get_exit_status()
Based on the comment by #KonradRudolph, I became aware of the processx R package that very smartly deals with system process submissions from within R.
All I had to do was:
library(processx)
down.command <- c("parallel","--gnu", "-a", "links.txt", "wget", ">", "~/down.log", "2>&1")
processx::process$new("nohup", down.comm, cleanup=FALSE)
As simple as that, and very effective.
Related
I can't start Rserve in debug mode.
I wrote these commands in R:
library(Rserve)
Rserve(debug=T, args="RS-enable-control", quote=T, port = 6311)
library(RSclient)
c=RSconnect(host = "localhost", port = 6311)
RSeval(c, "xx<-12")
RSeval(c, "2+6")
RSeval(c, "xx")
RSclose(c)
install.packages("fpc")
I placed the Rserve_d.exe in the same directory where the R.dll file is located. But when I launch it and I launch Tableau with the Rserve connection I can't see anything in the debug console, just these few lines.
Rserve 1.7-3 () (C)Copyright 2002-2013 Simon Urbanek
$Id$
Loading config file Rserv.cfg
Failed to find config file Rserv.cfg
Rserve: Ok, ready to answer queries.
-create_server(port = 6311, socket = <NULL>, mode = 0, flags = 0x4000)
INFO: adding server 000000000030AEE0 (total 1 servers)
I tried another solution by the command Rserve(TRUE) in R, but I can't see the transactions between R and Tableau neither in the Rstudio console.
I wanted then to print the output of the variable in R from the R-script function, by print(.arg1). But nothing appears in the R console
but when I run print in the R console it works fine.
According to this article*, RServe should be run with the following command to enable debugging:
R CMD Rserve_d
An alternative is to use the ‘write.csv’ command within the calculated field that calls an R script, as suggested by this FAQ document from Tableau
Starting Rserve_d.exe from command line works. Most likely you have multiple instances of Rserve running and Tableau is sending requests to one that is not Rserve_d running in the command line.
Did you try killing all Rserve processes and then starting Rserve_d from command line?
If you don't want to run from the command line you can try starting Rserve in process from RStudio by typing run.Rserve() then using print() statements in your Tableau calculated fields for things you want to print.
In the R bin directory, you have two executables Rserve for normal execution and Rserve.dbg for debug execution. Use
R CMD Rserve.dbg
My OS is CENTOS7 and I am using the R installation from anaconda. If your RServe debug executable has a different name you should be using that.
I want R to shutdown my computer after my (extensive) simulation and saving results, is this possible?
Yes, look at the function shutdown in the package fun.
The flags for system command shutdown depends on your operating system, the function simply calls the appropriately flagged command.
fun::shutdown
function (wait = 0)
{
Sys.sleep(wait)
ifelse(.Platform$OS.type == "windows", shell("shutdown -s -t 0"),
system("shutdown -h now"))
}
R can send commands to the system with ?system, and so whatever is required for Windows can be done with that:
http://www.microsoft.com/resources/documentation/windows/xp/all/proddocs/en-us/shutdown.mspx?mfr=true
R has a .Last() function controlled by quit() (or q()) with its runLast argument, so this is where you would send the shutdown commands via system, so that it occurs after quitting R. Saving objects with R is done with save or save.image, though there is a default to save as well with quit().
Executing
system("shutdown -s")
will shut your computer down. Just add it at the end of your script
I want R to shutdown my computer after my (extensive) simulation and saving results, is this possible?
Yes, look at the function shutdown in the package fun.
The flags for system command shutdown depends on your operating system, the function simply calls the appropriately flagged command.
fun::shutdown
function (wait = 0)
{
Sys.sleep(wait)
ifelse(.Platform$OS.type == "windows", shell("shutdown -s -t 0"),
system("shutdown -h now"))
}
R can send commands to the system with ?system, and so whatever is required for Windows can be done with that:
http://www.microsoft.com/resources/documentation/windows/xp/all/proddocs/en-us/shutdown.mspx?mfr=true
R has a .Last() function controlled by quit() (or q()) with its runLast argument, so this is where you would send the shutdown commands via system, so that it occurs after quitting R. Saving objects with R is done with save or save.image, though there is a default to save as well with quit().
Executing
system("shutdown -s")
will shut your computer down. Just add it at the end of your script
I have used R in the past to do very basic calls to the commmand line. The example can be found here.
This time around, I am looking to mimic this code which runs successfully from the command line in Windows:
> cd C:\Documents and Settings\BTIBERT\My Documents\My Dropbox\Eclipse\Projects\R\MLB\retrosheet\rawdata
> bgame -y 2010 2010bos.eva >2010bos.txt
This is the code I am trying to run inside of R. I have already set the working directory inside of R.
dir <- paste("cd", getwd(), sep=" ")
system(dir)
system("bgame -y 2010 2010bos.eva >2010bos.txt")
I am sure this is user error, but what am I doing wrong? It appears to work initially, but returns the following error. I very well could be doing something wrong, but I believe I am using the same commands.
Expanded game descriptor, version 109(185) of 05/08/2008.
Type 'bgame -h' for help.
Copyright (c) 2001 by DiamondWare.
[Processing file 2010bos.eva.]
>2010bos.txt: can't open.
Warning message:
running command 'bgame -y 2010 2010bos.eva >2010bos.txt' had status 2
Any help you can provide will be appreciated.
You need to issue all commands in one system() call:
system(paste("cd",getwd() "&& bgame -y 2010 2010bos.eva >2010bos.txt",sep=" "))
You should already be in your working directory, so I'm not sure the cd getwd() is necessary. And you may need quotes around your path because it contains spaces. The error may be resolved by putting spaces around >.
If I were in your shoes, I would try this:
system("bgame -y 2010 2010bos.eva > 2010bos.txt")
UPDATE:
And you should probably heed this advice in the "Differences between Unix and Windows" section of ?system that says you should use shell:
• The most important difference is that on a Unix-alike
‘system’ launches a shell which then runs ‘command’. On
Windows the command is run directly - use ‘shell’ for an
interface which runs ‘command’ _via_ a shell (by default the
Windows shell ‘cmd.exe’, which has many differences from the
POSIX shell).
This means that it cannot be assumed that redirection or
piping will work in ‘system’ (redirection sometimes does, but
we have seen cases where it stopped working after a Windows
security patch), and ‘system2’ (or ‘shell’) must be used on
Windows.
Has no-one else found that system("dir", intern = T) for example doesn't work, but that you need system("cmd.exe /c dir", intern = T)? Only the latter works for me. I found this at the discussion site here (William Dunlap's post, about a third of the way down).
Also, it doesn't work with the "cd" command, but you can use the setwd() function within R and then the command will be executed within that directory.
I created the following functions for convenience, for executing programmes and running commands:
#the subject is an input file that a programme might require
execute <- function(programme, subject.spec = "", intern = FALSE, wait = FALSE){
if(!identical(subject.spec, "")){subject.spec <- paste0(" ", subject.spec)} #put space before the subject if it exists
system(paste0("cmd.exe /c ", programme, subject.spec), intern = intern, wait = wait)
}
command <- function(command, intern = TRUE, wait = FALSE){
system(paste("cmd.exe /c", command), intern = T, wait = wait)
}
Does it break your code when you get error 1 or does execution continue?
Whenever executing system commands through another language it is useful to print the system call before you call it to see exactly what is happening, pull up the shell you are intending to use and check for the same error. As the command is executed correctly this could be a hickup in bgame or R.
If you look at http://astrostatistics.psu.edu/datasets/R/html/base/html/shell.html you can see the variable flag passed to the system call."flag the switch to run a command under the shell. If the shell is bash or tcsh the default is changed to "-c"."
Also "the shell to be used can be changed by setting the configure variable R_SHELL to a suitable value (a full path to a shell, e.g. /usr/local/bin/bash)."
I have written an R script that pulls some data from a database, performs several operations on it and post the output to a new database.
I would like this script to run every day at a specific time but I can not find any way to do this effectively.
Can anyone recommend a resource I could look at to solve this issue? I am running this script on a Windows machine.
Actually under Windows you do not even have to create a batch file first to use the Scheduler.
Open the scheduler: START -> All Programs -> Accesories -> System Tools -> Scheduler
Create a new Task
under tab Action, create a new action
choose Start Program
browse to Rscript.exe which should be placed e.g. here:
"C:\Program Files\R\R-3.0.2\bin\x64\Rscript.exe"
input the name of your file in the parameters field
input the path where the script is to be found in the Start in field
go to the Triggers tab
create new trigger
choose that task should be done each day, month, ... repeated several times, or whatever you like
Supposing your R script is mytest.r, located in D:\mydocuments\, you can create a batch file including the following command:
C:\R\R-2.10.1\bin\Rcmd.exe BATCH D:\mydocuments\mytest.r
Then add it, as a new task, to windows task scheduler, setting there the triggering conditions.
You could also omit the batch file. Set C:\R\R-2.10.1\bin\Rcmd.exe in the program/script textbox in task scheduler, and give as Arguments the rest of the initial command: BATCH D:\mydocuments\mytest.r
Scheduling R Tasks via Windows Task Scheduler (Posted on February 11, 2015)
taskscheduleR: R package to schedule R scripts with the Windows task manager (Posted on March 17, 2016)
EDIT
I recently adopted the use of batch files again, because I wanted the cmd window to be minimized (I couldn't find another way).
Specifically, I fill the windows task scheduler Actions tab as follows:
Program/script:
cmd.exe
Add arguments (optional):
/c start /min D:\mydocuments\mytest.bat ^& exit
Contents of mytest.bat:
C:\R\R-3.5.2\bin\x64\Rscript.exe D:\mydocuments\mytest.r params
Now there is built in option in RStudio to do this, to run scheduler first install below packages
install.packages('data.table')
install.packages('knitr')
install.packages('miniUI')
install.packages('shiny')
install.packages("taskscheduleR", repos = "http://www.datatailor.be/rcube", type =
"source")
After installing go to
**TOOLS -> ADDINS ->BROWSE ADDINS ->taskscheduleR -> Select it and execute it.**
Setting up the task scheduler
Step 1) Open the task scheduler (Start > search Task Scheduler)
Step 2) Click "Action" > "Create Task"
Step 3) Select "Run only when the user is logged on", uncheck "Run with highest priveledges", name your task,
configure for "Windows Vista/Windows Server 2008"
Step 4) Under the "Triggers" tab, set when you would like the script to run
Step 5) Under the "Actions" tab, put the full location of the Rscript.exe file, i.e.
"C:\Program Files\R\R-3.6.2\bin\Rscript.exe" (include the quotes)
Put the name of your script with with -e and source() in arguments wrapping it like this:
-e "source('C:/location_of_my_script/test.R')"
Troubleshooting a Rscript scheduled in the Task Scheduler
When you run a script using the Task Scheduler, it is difficult to troubleshoot any issues because you don't get any error messages.
This can be resolved by using the sink() function in R which will allow you to output all error messages to a file that you specify. Here is how you can do this:
# Set up error log ------------------------------------------------------------
error_log <- file("C:/location_of_my_script/error_log.Rout", open="wt")
sink(error_log, type="message")
try({
# insert your code here
})
The other thing that you will have to change to make your Rscript work is to specify the full file path of any file paths in your script.
This will not work in task scheduler:
source("./functions/import_function.R")
You will need to specify the full file path of any scripts you are sourcing within your Rscript:
source("C:/location_of_my_script/functions/import_function.R")
Additionally, I would remove any special characters from any file paths that you are referencing in your R script. For example:
df <- fread("C:/location_of_my_data/file#2342.csv")
may not run. Instead, try:
df <- fread("C:/location_of_my_data/file_2342.csv")
Changing windows passwords
Beware: Changing windows passwords will pause your task scheduler script(s). You will need to log back into the task scheduler and enter your password to get them started again.
I set up my tasks via the SCHTASKS program. For running scripts on startup, you would write something along the lines of
SCHTASKS /Create /SC ONSTART /TN MyProgram /TR "R CMD BATCH --vanilla d:\path\to\script.R"
See this website for more details on SCHTASKS. More details at Microsoft's website.
You can use Windows Task Scheduler.
After following any combination of these steps and you receive the "Argument Batch Ignored" error after R.exe runs, try this, it worked for me.
In Windows Task Scheduler:
Replace BATCH "C:\Users\desktop\yourscript.R"in the arguments field
with
CMD BATCH --vanilla --slave "C:\Users\desktop\yourscript.R"