ROOT   6.14/05 Reference Guide
ROOT::R::TRInterface Class Reference

ROOT R was implemented using the R Project library and the modules Rcpp and RInside

## TRInterface class

The TRInterface class lets you procces R code from ROOT.
You can call R libraries and their functions, plot results in R or ROOT,
and use the power of ROOT and R at the same time.
It also lets you pass scalars, vectors and matrices from ROOT to R
and from R to ROOT using TRObject; but you can to use overloaded opetarors [],<< and >>
to work with ROOTR like work with streams of data.

TRInterface class can not be instantiated directly, but you can create objects using the static methods TRInterface& Instance() and TRInterface* InstancePtr() to create your own objects.

Show an example below: Create an exponential fit, the idea is to create a set of numbers x,y with noise from ROOT, pass them to R and fit the data to $$x^3$$, get the fitted coefficient(power) and plot the data, the known function and the fitted function.

TCanvas *c1 = new TCanvas("c1","Curve Fit",700,500);
c1->SetGrid();
// draw a frame for multiples graphs
// create the first graph (points with gaussian noise)
const Int_t n = 24;
Double_t x[n] ;
//Generate points along a X^3 with noise
rg.SetSeed(520);
for (Int_t i = 0; i < n; i++) {
x[i] = rg.Uniform(0, 1);
y[i] = TMath::Power(x[i], 3) + rg.Gaus() * 0.06;
}
TGraph *gr1 = new TGraph(n,x,y);
gr1->SetMarkerSize(1);
// create second graph
TF1 *f_known=new TF1("f_known","pow(x,3)",0,1);
TGraph *gr2 = new TGraph(f_known);
gr2->SetMarkerSize(1);
//passing x and y values to R for fitting
r["x"]<<TVectorD(n, x);
r["y"]<<TVectorD(n, y);
//creating a R data frame
r<<"ds<-data.frame(x=x,y=y)";
//fitting x and y to X^power using Nonlinear Least Squares
r<<"m <- nls(y ~ I(x^power),data = ds, start = list(power = 1),trace = T)";
//getting the fitted value (power)
Double_t power;
r["summary(m)\$coefficients[1]"]>>power;
TF1 *f_fitted=new TF1("f_fitted","pow(x,[0])",0,1);
f_fitted->SetParameter(0,power);
//plotting the fitted function
TGraph *gr3 = new TGraph(f_fitted);
gr3->SetMarkerSize(1);
mg->Draw("ap");
//displaying basic results
TPaveText *pt = new TPaveText(0.1,0.6,0.5,0.9,"brNDC");
pt->SetFillColor(18);
pt->SetTextAlign(12);
pt->AddText(" \"Blue\" Points with gaussian noise to be fitted");
TString fmsg;
fmsg.Form(" \"Green\" Fitted function with power=%.4lf",power);
pt->Draw();
c1->Update();

## Users Guide

Definition at line 137 of file TRInterface.h.

class  Binding

## Public Member Functions

~TRInterface ()

template<typename T >
void Assign (const T &var, const TString &name)
Template method to assign C++ variables into R enviroment. More...

void Assign (const TRFunctionExport &fun, const TString &name)
Method to assign TRFunctionExport in R's enviroment. More...

void Assign (const TRDataFrame &df, const TString &name)
Method to assign TRDataFrame in R's enviroment. More...

Int_t Eval (const TString &code, TRObject &ans)
Method to eval R code and you get the result in a reference to TRObject. More...

TRObject Eval (const TString &code)
Method to eval R code and you get the result in a TRObject. More...

void Execute (const TString &code)
Method to eval R code. More...

Bool_t Install (TString pkg, TString repos="http://cran.r-project.org")
Method to install an R's package. More...

void Interactive ()
Method to get a R prompt to work interactively with tab completation support. More...

Bool_t IsInstalled (TString pkg)
Method to verify if a package is installed. More...

Binding operator[] (const TString &name)

void ProcessEventsLoop ()
Init event loop in a thread to support actions in windows from R graphics system. More...

Bool_t Require (TString pkg)
Method to load an R's package. More...

void SetVerbose (Bool_t status)
Method to set verbose mode, that produce extra output. More...

Public Member Functions inherited from TObject
TObject ()
TObject constructor. More...

TObject (const TObject &object)
TObject copy ctor. More...

virtual ~TObject ()
TObject destructor. More...

void AbstractMethod (const char *method) const
Use this method to implement an "abstract" method that you don't want to leave purely abstract. More...

Append graphics object to current pad. More...

virtual void Browse (TBrowser *b)
Browse object. May be overridden for another default action. More...

ULong_t CheckedHash ()
Checked and record whether for this class has a consistent Hash/RecursiveRemove setup (*) and then return the regular Hash value for this object. More...

virtual const char * ClassName () const
Returns name of class to which the object belongs. More...

virtual void Clear (Option_t *="")

virtual TObjectClone (const char *newname="") const
Make a clone of an object using the Streamer facility. More...

virtual Int_t Compare (const TObject *obj) const
Compare abstract method. More...

virtual void Copy (TObject &object) const
Copy this to obj. More...

virtual void Delete (Option_t *option="")
Delete this object. More...

virtual Int_t DistancetoPrimitive (Int_t px, Int_t py)
Computes distance from point (px,py) to the object. More...

virtual void Draw (Option_t *option="")
Default Draw method for all objects. More...

virtual void DrawClass () const
Draw class inheritance tree of the class to which this object belongs. More...

virtual TObjectDrawClone (Option_t *option="") const
Draw a clone of this object in the current selected pad for instance with: gROOT->SetSelectedPad(gPad). More...

virtual void Dump () const
Dump contents of object on stdout. More...

virtual void Error (const char *method, const char *msgfmt,...) const
Issue error message. More...

virtual void Execute (const char *method, const char *params, Int_t *error=0)
Execute method on this object with the given parameter string, e.g. More...

virtual void Execute (TMethod *method, TObjArray *params, Int_t *error=0)
Execute method on this object with parameters stored in the TObjArray. More...

virtual void ExecuteEvent (Int_t event, Int_t px, Int_t py)
Execute action corresponding to an event at (px,py). More...

virtual void Fatal (const char *method, const char *msgfmt,...) const
Issue fatal error message. More...

virtual TObjectFindObject (const char *name) const
Must be redefined in derived classes. More...

virtual TObjectFindObject (const TObject *obj) const
Must be redefined in derived classes. More...

virtual Option_tGetDrawOption () const
Get option used by the graphics system to draw this object. More...

virtual const char * GetIconName () const
Returns mime type name of object. More...

virtual const char * GetName () const
Returns name of object. More...

virtual char * GetObjectInfo (Int_t px, Int_t py) const
Returns string containing info about the object at position (px,py). More...

virtual Option_tGetOption () const

virtual const char * GetTitle () const
Returns title of object. More...

virtual UInt_t GetUniqueID () const
Return the unique object id. More...

virtual Bool_t HandleTimer (TTimer *timer)
Execute action in response of a timer timing out. More...

virtual ULong_t Hash () const
Return hash value for this object. More...

Bool_t HasInconsistentHash () const
Return true is the type of this object is known to have an inconsistent setup for Hash and RecursiveRemove (i.e. More...

virtual void Info (const char *method, const char *msgfmt,...) const
Issue info message. More...

virtual Bool_t InheritsFrom (const char *classname) const
Returns kTRUE if object inherits from class "classname". More...

virtual Bool_t InheritsFrom (const TClass *cl) const
Returns kTRUE if object inherits from TClass cl. More...

virtual void Inspect () const
Dump contents of this object in a graphics canvas. More...

void InvertBit (UInt_t f)

virtual Bool_t IsEqual (const TObject *obj) const
Default equal comparison (objects are equal if they have the same address in memory). More...

virtual Bool_t IsFolder () const
Returns kTRUE in case object contains browsable objects (like containers or lists of other objects). More...

R__ALWAYS_INLINE Bool_t IsOnHeap () const

virtual Bool_t IsSortable () const

R__ALWAYS_INLINE Bool_t IsZombie () const

virtual void ls (Option_t *option="") const
The ls function lists the contents of a class on stdout. More...

void MayNotUse (const char *method) const
Use this method to signal that a method (defined in a base class) may not be called in a derived class (in principle against good design since a child class should not provide less functionality than its parent, however, sometimes it is necessary). More...

virtual Bool_t Notify ()
This method must be overridden to handle object notification. More...

void Obsolete (const char *method, const char *asOfVers, const char *removedFromVers) const
Use this method to declare a method obsolete. More...

void operator delete (void *ptr)
Operator delete. More...

void operator delete[] (void *ptr)
Operator delete []. More...

voidoperator new (size_t sz)

voidoperator new (size_t sz, void *vp)

voidoperator new[] (size_t sz)

voidoperator new[] (size_t sz, void *vp)

TObjectoperator= (const TObject &rhs)
TObject assignment operator. More...

virtual void Paint (Option_t *option="")
This method must be overridden if a class wants to paint itself. More...

virtual void Pop ()
Pop on object drawn in a pad to the top of the display list. More...

virtual void Print (Option_t *option="") const
This method must be overridden when a class wants to print itself. More...

virtual Int_t Read (const char *name)
Read contents of object with specified name from the current directory. More...

virtual void RecursiveRemove (TObject *obj)
Recursively remove this object from a list. More...

void ResetBit (UInt_t f)

virtual void SaveAs (const char *filename="", Option_t *option="") const
Save this object in the file specified by filename. More...

virtual void SavePrimitive (std::ostream &out, Option_t *option="")
Save a primitive as a C++ statement(s) on output stream "out". More...

void SetBit (UInt_t f, Bool_t set)
Set or unset the user status bits as specified in f. More...

void SetBit (UInt_t f)

virtual void SetDrawOption (Option_t *option="")
Set drawing option for object. More...

virtual void SetUniqueID (UInt_t uid)
Set the unique object id. More...

virtual void SysError (const char *method, const char *msgfmt,...) const
Issue system error message. More...

R__ALWAYS_INLINE Bool_t TestBit (UInt_t f) const

Int_t TestBits (UInt_t f) const

virtual void UseCurrentStyle ()
Set current style settings in this object This function is called when either TCanvas::UseCurrentStyle or TROOT::ForceStyle have been invoked. More...

virtual void Warning (const char *method, const char *msgfmt,...) const
Issue warning message. More...

virtual Int_t Write (const char *name=0, Int_t option=0, Int_t bufsize=0)
Write this object to the current directory. More...

virtual Int_t Write (const char *name=0, Int_t option=0, Int_t bufsize=0) const
Write this object to the current directory. More...

## Static Public Member Functions

static TRInterfaceInstance ()
static method to get an TRInterface instance reference More...

static TRInterfaceInstancePtr ()
static method to get an TRInterface instance pointer More...

Static Public Member Functions inherited from TObject
static Long_t GetDtorOnly ()
Return destructor only flag. More...

static Bool_t GetObjectStat ()
Get status of object stat flag. More...

static void SetDtorOnly (void *obj)
Set destructor only flag. More...

static void SetObjectStat (Bool_t stat)
Turn on/off tracking of objects in the TObjectTable. More...

RInside * fR

## Private Member Functions

TRInterface (const Int_t argc=0, const Char_t *argv[]=NULL, const Bool_t loadRcpp=true, const Bool_t verbose=false, const Bool_t interactive=true)
The command line arguments are by deafult argc=0 and argv=NULL, The verbose mode is by default disabled but you can enable it to show procedures information in stdout/stderr. More...

Public Types inherited from TObject
enum  {
kIsOnHeap = 0x01000000, kNotDeleted = 0x02000000, kZombie = 0x04000000, kInconsistent = 0x08000000,
}

enum  { kSingleKey = BIT(0), kOverwrite = BIT(1), kWriteDelete = BIT(2) }

enum  EDeprecatedStatusBits { kObjInCanvas = BIT(3) }

enum  EStatusBits {
kCanDelete = BIT(0), kMustCleanup = BIT(3), kIsReferenced = BIT(4), kHasUUID = BIT(5),
kCannotPick = BIT(6), kNoContextMenu = BIT(8), kInvalidObject = BIT(13)
}

Protected Member Functions inherited from TObject
virtual void DoError (int level, const char *location, const char *fmt, va_list va) const
Interface to ErrorHandler (protected). More...

void MakeZombie ()

#include <TRInterface.h>

Inheritance diagram for ROOT::R::TRInterface:
[legend]

## ◆ TRInterface()

 TRInterface::TRInterface ( const Int_t argc = 0, const Char_t * argv[] = NULL, const Bool_t loadRcpp = true, const Bool_t verbose = false, const Bool_t interactive = true )
private

The command line arguments are by deafult argc=0 and argv=NULL, The verbose mode is by default disabled but you can enable it to show procedures information in stdout/stderr.

Note
some time can produce so much noise in the output
Parameters
 argc default 0 args default null loadRcpp default true verbose default false interactive default true

Definition at line 25 of file TRInterface.cxx.

## ◆ ~TRInterface()

 TRInterface::~TRInterface ( )

Definition at line 54 of file TRInterface.cxx.

## ◆ Assign() [1/3]

template<typename T >
 void ROOT::R::TRInterface::Assign ( const T & var, const TString & name )
inline

Template method to assign C++ variables into R enviroment.

Parameters
 var any R wrappable datatype name name of the variable in R's enviroment

Definition at line 255 of file TRInterface.h.

## ◆ Assign() [2/3]

 void TRInterface::Assign ( const TRFunctionExport & fun, const TString & name )

Method to assign TRFunctionExport in R's enviroment.

Parameters
 fun TRFunctionExport name name of the variable in R's enviroment

Definition at line 131 of file TRInterface.cxx.

## ◆ Assign() [3/3]

 void TRInterface::Assign ( const TRDataFrame & df, const TString & name )

Method to assign TRDataFrame in R's enviroment.

Parameters
 df TRDataFrame name name of the variable in R's enviroment

Definition at line 137 of file TRInterface.cxx.

## ◆ Eval() [1/2]

 Int_t TRInterface::Eval ( const TString & code, TRObject & ans )

Method to eval R code and you get the result in a reference to TRObject.

Parameters
 code R code ands reference to TRObject
Returns
an true or false if the execution was sucessful or not.

Definition at line 63 of file TRInterface.cxx.

## ◆ Eval() [2/2]

 TRObject TRInterface::Eval ( const TString & code )

Method to eval R code and you get the result in a TRObject.

Parameters
 code R code
Returns
a TRObject with result

Definition at line 96 of file TRInterface.cxx.

## ◆ Execute()

 void TRInterface::Execute ( const TString & code )

Method to eval R code.

Parameters
 code R code

Definition at line 82 of file TRInterface.cxx.

## ◆ Install()

 Bool_t TRInterface::Install ( TString pkg, TString repos = "http://cran.r-project.org" )

Method to install an R's package.

Parameters
 pkg R's pkg name repos url for R's package repository
Returns
true or false if the package was installed or not

Definition at line 190 of file TRInterface.cxx.

## ◆ Instance()

 TRInterface & TRInterface::Instance ( )
static

static method to get an TRInterface instance reference

Returns
TRInterface instance reference

Definition at line 170 of file TRInterface.cxx.

## ◆ InstancePtr()

 TRInterface * TRInterface::InstancePtr ( )
static

static method to get an TRInterface instance pointer

Returns
TRInterface instance pointer

Definition at line 158 of file TRInterface.cxx.

## ◆ Interactive()

 void TRInterface::Interactive ( )

Method to get a R prompt to work interactively with tab completation support.

Definition at line 144 of file TRInterface.cxx.

## ◆ IsInstalled()

 Bool_t TRInterface::IsInstalled ( TString pkg )

Method to verify if a package is installed.

Parameters
 pkg R's pkg name
Returns
true or false if the package is installed or not

Definition at line 176 of file TRInterface.cxx.

## ◆ operator[]()

 TRInterface::Binding TRInterface::operator[] ( const TString & name )

Definition at line 125 of file TRInterface.cxx.

## ◆ ProcessEventsLoop()

 void TRInterface::ProcessEventsLoop ( )

Init event loop in a thread to support actions in windows from R graphics system.

Definition at line 202 of file TRInterface.cxx.

## ◆ Require()

 Bool_t TRInterface::Require ( TString pkg )

Method to load an R's package.

Parameters
 pkg R's pkg name
Returns
true or false if the package was loaded or not

Definition at line 183 of file TRInterface.cxx.

## ◆ SetVerbose()

 void TRInterface::SetVerbose ( Bool_t status )

Method to set verbose mode, that produce extra output.

Note
some time can produce so much noise in the output
Parameters
 status boolean to enable of disable

Definition at line 117 of file TRInterface.cxx.

## ◆ fR

 RInside* ROOT::R::TRInterface::fR
protected

Definition at line 139 of file TRInterface.h.