Calling R From SAS

The statistics literature is filled with example code and sample data in R. Sometimes I find myself wanting to work through some provided sample data and compare the output from R with SAS code. In this post, I’ll show how to connect R and SAS so that you can load and execute R code straight from within SAS.

Setup

In order to use this feature, you will want to have both R and SAS/IML installed on the same computer. Make sure both SAS and R are in your path. In order to call R code from SAS, you will need to start SAS with the rlang option. You can call SAS from the command line with the -rlang option or you can add the option in your “sasv9.cfg” file.

Once SAS is started, you can verify that the setup worked by running

proc options option=rlang;
run;

The log will list RLANG if the option was specified. If you forgot to add the option prior to startup, you’ll see NORLANG in the log instead.

Usage

R code can be called from within IML via a submit statement. The basic structure is this:

proc iml;
  submit / R;
    /* R code her */
  endsubmit;
quit;

With this we can run R code from within SAS. But the real power comes from our ability to move data between R and SAS. The following functions are available:

• ExportDatasetToR("libname.dsname", RDataFrame);
• ExportMatrixToR(IMLMatrix, RMatrix);
• ImportDataSetFromR(r-expr, "libname.dsname")
• ImportMatrixFromR(r-expr, IMLMatrix)

Parameters can be passed to R as well, similar to how parameters can be passed from IML to SAS PROCs.

For more details, see the SAS/IML manual.