NAME Statistics::R - Perl interface with the R statistical program DESCRIPTION *Statistics::R* is a module to controls the R interpreter (R project for statistical computing: ). It lets you start R, pass commands to it and retrieve the output. A shared mode allow to have several instances of *Statistics::R* talk to the same R process. The current *Statistics::R* implementation uses pipes (for stdin, stdout and and stderr) to communicate with R. This implementation should be more efficient and reliable than that in previous version, which relied on reading and writing files. As before, this module works on GNU/Linux, MS Windows and probably many more systems. SYNOPSIS use Statistics::R; # Create a communication bridge with R and start R my $R = Statistics::R->new(); # Run simple R commands my $output_file = ""; $R->run(qq`postscript("$output_file" , horizontal=FALSE , width=500 , height=500 , pointsize=1)`); $R->run(q`plot(c(1, 5, 10), type = "l")`); $R->run(q``); # Pass and retrieve data (scalars or arrays) my $input_value = 1; $R->set('x', $input_value); $R->run(q`y <- x^2`); my $output_value = $R->get('y'); print "y = $output_value\n"; $R->stop(); METHODS new() Build a *Statistics::R* bridge object between Perl and R. Available options are: r_bin Specify the full path to R if it is not automatically found. See INSTALLATION. shared Start a shared bridge. When using a shared bridge, several instances of Statistics::R can communicate with the same unique R instance. Example: use Statistics::R; my $R1 = Statistics::R->new( shared => 1); my $R2 = Statistics::R->new( shared => 1); $R1->set( 'x', 'pear' ); my $x = $R2->get( 'x' ); print "x = $x\n"; Do not call the *stop()* method is you still have processes that need to interact with R. run() First, start() R if it is not yet running. Then, execute R commands passed as a string and return the output as a string. If your command fails to run in R, an error message will be displayed. Example: my $out = $R->run( q`print( 1 + 2 )` ); If you intend on runnning many R commands, it may be convenient to pass an array of commands or put multiple commands in an here-doc: # Array of R commands: my $out1 = $R->run( q`a <- 2`, q`b <- 5`, q`c <- a * b`, q`print("ok")` ); # Here-doc with multiple R commands: my $cmds = <run($cmds); To run commands from a file, see the run_from_file() method. The output you get from run() is the combination of what R would display on the standard output and the standard error, but the order may differ. When loading modules, some may write numerous messages on standard error. You can disable this behavior using the following R command: suppressPackageStartupMessages(library(library_to_load)) run_from_file() Similar to run() but reads the R commands from the specified file. Internally, this method uses the R source() command to read the file. set() Set the value of an R variable (scalar or arrayref). Example: $R->set( 'x', 'pear' ); or $R->set( 'y', [1, 2, 3] ); get() Get the value of an R variable (scalar or arrayref). Example: my $x = $R->get( 'x' ); # $y is a scalar or my $y = $R->get( 'y' ); # $x is an arrayref start() Explicitly start R. Most times, you do not need to do that because the first execution of run() or set() will automatically call start(). stop() Stop a running instance of R. restart() stop() and start() R. bin() Get or set the path to the R executable. is_shared() Was R started in shared mode? is_started() Is R running? pid() Return the pid of the running R process INSTALLATION Since *Statistics::R* relies on R to work, you need to install R first. See this page for downloads, . If R is in your PATH environment variable, then it should be available from a terminal and be detected automatically by *Statistics::R*. This means that you don't have to do anything on Linux systems to get *Statistics::R* working. On Windows systems, in addition to the folders described in PATH, the usual suspects will be checked for the presence of the R binary, e.g. C:\Program Files\R. If *Statistics::R* does not find R installation, your last recourse is to specify its full path when calling new(): my $R = Statistics::R->new( r_bin => $fullpath ); You also need to have the following CPAN Perl modules installed: Text::Balanced (>= 1.97) Regexp::Common IPC::Run SEE ALSO * Statistics::R::Win32 * Statistics::R::Legacy * The R-project web site: * Statistics:: modules for Perl: AUTHORS Florent Angly (2011 rewrite) Graciliano M. P. (original code) MAINTAINER Brian Cassidy COPYRIGHT & LICENSE This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself. BUGS All complex software has bugs lurking in it, and this program is no exception. If you find a bug, please report it on the CPAN Tracker of Statistics::R: Bug reports, suggestions and patches are welcome. The Statistics::R code is developed on Github () and is under Git revision control. To get the latest revision, run: git clone