RObject methods

You can get RObject using R facade predefined object in JavaScript.

Each RObject object provides the set of methods:

·	void newSession () - create new R session, all variables in previous context will be removed.

Example:

r.newSession();

·	void saveSession (String name) - associate current context with name and save it on file system. Context can be restored later with openSession function

Example:

r.saveSession("e;mySession"e;);

·	void openSession (String name) - remove current R variables and load context from file system by name.

Example:

r.openSession("e;mySession"e;);

·	void voidEval (String expression) - evaluate R expression in R environment without result returning.

Example:

r.voidEval("e;a <- 10"e;); //create variable in R context with integer value

·	REXP eval (String expression) - evaluate R expression in R environment. The parameter of this method is string with R script and it returns object as a result of the last R commend.

Example:

var d = rObject.eval("e;rnorm(2)"e;); //return array of double

·	void assignObject (String varName, Object value) - assign Javascript object to R environment with specified variable name.

Example:

rObject.assignObject("e;a"e;, [1,2,3]); //add array variable "e;a"e; to R environment

·	void help (String expression) - looks for help in R environment and display it in BioUML environment.

Example:

rObject.help("e;data"e;); //display Data Sets help page from R

Complete example

Here is a complete JavaScript example of R session in BioUML.

var rObject = R.connect("e;server.biouml.org"e;, 80); //get remote RObject

print(rObject); //print rObject to check R availability

rObject.newSession(); //clean R context

rObject.voidEval("e;x=0;for(i in 1:100) {x = x+i;}); //execute set of commands

var x = rObject.eval("e;x"e;); //get x value from R

print(x); //print the result to console

rObject.saveSession("e;testSession"e;); //save current variables state

To use x variable value next time you can use script like this:

var rObject = R.connect("e;server.biouml.org"e;, 80); //get remote RObject

rObject.openSession("e;testSession"e;); //load saved R session

var x = rObject.eval("e;x"e;); //get variable from R

print(x); //print x value to console