Is it possible to change the behaviour of R console such that, for instance
before each command execution a fortune() is printed, or
similar to browser(), the prompt is altered, and some new commands (c,n,Q) are introduced?
I am looking for an alternative to readline() that keeps the history function (key up) intact.
I am using R on winxp with Rgui, but a portable solution would be great.
Yes, though it is independent of the GUI as just uses the callback mechanism as for example in the quesion on R: Display a time clock in the R command line.
Related
I have just started to learn to code on R, so I apologize for the very simple question. I understand it is best to type your code in as a Script so you can edit and save it. However, when I try to make an object in the script section, it does not work. If I make an object in the console, R saves the object and it appears in my environment. I am typing in a very simple code to try a quick exercise on rolling dice:
die <- 1:6
But it only works in the console and not when typed as a script. Any help/explanation appreciated!
Essentially, you interact with R environment differently when running an .R script via RScript.exe or via console with R.exe, Rterm, etc. and in GUI IDEs like RGui or RStudio. (This applies to any programming language with interactive compilers not just R).
The script does save thedie object in R environment but only during the run or lifetime of that script (i.e., from beginning to end of code lines). Your code line is simply an assignment of object. You do nothing with it. Apply some function, output results, and other actions in that script to see.
On the console, the R environment persists interactively until you quit it with q(). So assigned objects remains for lifetime of your console session. After assigning, you can afterwards apply function, output results, or other actions in line by line calls.
Ultimately, scripts gathers all line by line code in advance of run for automated execution without relying on user to supply lines. Imagine running 1,000 lines of code with nested if/then or for/while loops, apply functions on console! Therefore, have all your R coding needs summarily handled in scripts.
It is always better to have the script, as you say, you can save edit correct, without having to rewrite the code to change a variable or number.
I recommend using Rstudio, it is very practical and will help you to program more efficiently and allows you to see, among other things, the different objects that you have created.
I'm trying to call a simple python script from within R using system2(). I've read some information I found vague that said if 'too much' memory is used, it won't work.
If I load a large dataset and use some information in it to use as arguments to pass into system2(), it will only work if I manually click "Restart R" in call Rstudio.
What I want:
df <- read.csv('some_large_file.csv')
###extracting some info called 'args_vec'
for(arg in args_vec){
system2('python', args)
}
This won't work as is. The for loop is simply passed over.
What I need:
df <- read.csv('some_large_file.csv')
###extracting some info called 'args_vec'
###something that 'restarts' R
for(arg in args_vec){
system2('python', args)
}
This answer doesn't quite get what I want. Namely, it doesn't work for me within Rstudio and it calls "system" (which presents the same problem as "system2" in this case). In fact, when I put the answer referenced above in my Rprofile.site file, it just immediately closed rstudio:
I tried the suggestion as a normal function (rather than using "makeActiveBinding", and it didn't quite work.
##restart R in r session -- doesn't work
makeActiveBinding("refresh", function() { system("R --save"); q("no") }, .GlobalEnv)
##nor did this:
refresh <- function() { system("R --save"); q("no") }
I tried a number of variations of these two options above, but this is getting long for what feels like a simple question. There's a lot I don't yet understand about the startup process and "makeActiveBinding" is a bit mysterious. Can anyone point me in the right direction?
In Rstudio, you can restart the R session by:
command/ctrl + shift + F10
You can also use:
.rs.restartR()
RStudio has this undocumented rs.restartR() which is supposed to do just that: restarting R.
However, it does not unload the packages that were loaded, nor does it clean the environment, so that I have some doubts about if it restarts R at all.
If you use RStudio, use the menu item Session > Restart R or the associated keyboard shortcut Ctrl+Shift+F10 (Windows and Linux) or Command+Shift+F10 (Mac OS). Additional keyboard shortcuts make it easy to restart development where you left off, i.e. to say “re-run all the code up to HERE”:
In an R script, use Ctrl+Alt+B (Windows and Linux) or Command+Option+B (Mac OS)
In R markdown, use Ctrl+Alt+P (Windows and Linux) or Command+Option+P (Mac OS)
If you run R from the shell, use Ctrl+D or q() to quit, then restart R.
Have you tried embedding the function call within the apply function, rather than a for loop?
I've had some pieces of code that ran the system out of memory in a for loop run perfectly with apply. It might help?
For those not limited to a command that want something that actually resets the system (no prior state, no loaded packages, no variables, etc.) you can select Terminate R from the Session menu.
It is a bit awkward (asks you if you are sure). If anyone knows something like clear all or really clear classes in MATLAB let me know!
I just got ESS set up in EMACS (I'm a relative newbie in this area). I have figured out how to take an R script and fire up an interactive R shell and evaluate a whole buffer ("C-c C-b"). But I'd also like to have the ability to submit an R script via RScript in the way that you can with Perl or Python with `compile-dwim-run', which I have bound to "C-c r", and have the whole output returned to me in a separate buffer without keeping open an interactive R shell.
I can't seem to find a default way to do this, and I'd like to leverage whatever ESS has to work that (I assume there is) before I go off and attempt to roll my own.
Thank you,
Matt
C-c C-l is what you are looking for? Use C-c C-h to see all the keys that are bound on C-c map (an even better approach is to install helm-descrbind from emacs package manager - you will be pleasantly surprised :).
[edit:] Sorry, misread your post slightly. You want batch evaluation. That is not available for R. The reason, the analysis in R is usually a complex process which you don't want to execute again and again. So you keep your interactive session open and iteratively achieve what you want.
There have been talks inside ESS to add some batch functionality, but it seems like very few people really need that.
I am running a set of selected code on R. Like
source("/tmp/r-plugin-honli/Rsource-2704-quantmod.R")
There is no output. Only the prompt '>' flickered there.
I use 'killall' to kill the R session. But I don't know where is wrong on the code. Because R did not give any output. How could I know what's going on about the code.
I'd try two things:
Run the code interactively. As in, open the Rsource-2704 file and run its lines one by one.
If that doesn't replicate the problem or is not possible, you can take Joshua Ulrich's suggestion or use:
R CMD BATCH --vanilla Rsource-2704-quantmod.R out.log
Which will run the code in a batch mode and output the usual console lines to a file called out.log (you can name it whatever you like).
Instead of using print statements, you could also take a look at the browser() command. This drops you into an interactive session at the point where the command is put. This works particularly well when trying to figure out what is happening inside a function, although I don't know if your script contains them.
Is there an easy way to turn of all GUI elements in R and run it solely from the command line on OSX?
I'm trying to replicate the behavior of a remote linux terminal on my OSX machine. Thus plot() should just save a file and things like CRAN mirror selection should be text, not a Tk interface. I'm having trouble finding where to set this behavior.
I had this exact question and wanted a way to do it without changing my existing code. I usually run with graphics support but sometimes I'll run a script on the server for a larger dataset and then I just want the plots to be output somewhere automatically.
In Dirk's answer Ian Fellows gives the simple solution. On the command line in R type:
options(device=pdf)
And then any plots will be written to the current directly to an Rplots.pdf file.
If you want the files to not be plotted at all then use
options(device=NULL)
For the plots you can just direct the output to a file using the pdf() command (or png(), jpeg()...).
I don't own an OS X box, but did you try to unset the X11 environment variable DISPLAY:
DISPLAY="" R --vanilla
When I do that on Linux and query R for capabilties(), x11 comes up as FALSE as desired.
I don't run OSX but you could attempt to run R from the Terminal application, rather than the Mac OSX launcher, and see whether that runs as you need.
As Matti writes, you can send output to files using the following commands; but I don't know if that's really the substance of your question.
png("pngfile.png")
plot(foo)
title(main="bar")
dev.off()
So instead of the quartz graphical object, your output goes to the file.
Similarly, you can output what would normally appear in the terminal to a file.
sink("foo.file")