RooRealVar.cxx

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/*****************************************************************************
 * Project: RooFit                                                           *
 * Package: RooFitCore                                                       *
 * @(#)root/roofitcore:$Id$
 * Authors:                                                                  *
 *   WV, Wouter Verkerke, UC Santa Barbara, verkerke@slac.stanford.edu       *
 *   DK, David Kirkby,    UC Irvine,         dkirkby@uci.edu                 *
 *                                                                           *
 * Copyright (c) 2000-2005, Regents of the University of California          *
 *                          and Stanford University. All rights reserved.    *
 *                                                                           *
 * Redistribution and use in source and binary forms,                        *
 * with or without modification, are permitted according to the terms        *
 * listed in LICENSE (http://roofit.sourceforge.net/license.txt)             *
 *****************************************************************************/
 
/**
\file RooRealVar.cxx
\class RooRealVar
\ingroup Roofitcore
 
Variable that can be changed from the outside.
For example by the user or a fitter.
 
It can be written into datasets, can hold a (possibly asymmetric) error, and
can have several ranges. These can be accessed with names, to e.g. limit fits
or integrals to sub ranges. The range without any name is used as default range.
**/
 
#include "RooRealVar.h"
 
#include "RooStreamParser.h"
#include "RooErrorVar.h"
#include "RooRangeBinning.h"
#include "RooCmdConfig.h"
#include "RooMsgService.h"
#include "RooParamBinning.h"
#include "RooVectorDataStore.h"
#include "RooTrace.h"
#include "RooRealVarSharedProperties.h"
#include "RooUniformBinning.h"
#include "RooSentinel.h"
 
#include "TTree.h"
#include "TBuffer.h"
#include "TBranch.h"
#include "snprintf.h"
 
using std::endl, std::ostream, std::istream;
 
 
 
bool RooRealVar::_printScientific(false) ;
Int_t  RooRealVar::_printSigDigits(5) ;
 
static bool staticSharedPropListCleanedUp = false;
 
/// Return a reference to a map of weak pointers to RooRealVarSharedProperties.
RooRealVar::SharedPropertiesMap* RooRealVar::sharedPropList()
{
  RooSentinel::activate();
  if(!staticSharedPropListCleanedUp) {
    static auto * staticSharedPropList = new SharedPropertiesMap{};
    return staticSharedPropList;
  }
  return nullptr;
}
 
////////////////////////////////////////////////////////////////////////////////
/// Explicitly deletes the shared properties list on exit to avoid problems
/// with the initialization order. Meant to be only used internally in RooFit
/// by RooSentinel.
 
void RooRealVar::cleanup()
{
  if(sharedPropList()) {
    delete sharedPropList();
    staticSharedPropListCleanedUp = true;
  }
}
 
////////////////////////////////////////////////////////////////////////////////
 
/// Return a dummy object to use when properties are not initialised.
RooRealVarSharedProperties& RooRealVar::_nullProp()
{
  static const std::unique_ptr<RooRealVarSharedProperties> nullProp(new RooRealVarSharedProperties("00000000-0000-0000-0000-000000000000"));
  return *nullProp;
}
 
////////////////////////////////////////////////////////////////////////////////
/// Default constructor.
 
RooRealVar::RooRealVar()  :  _error(0), _asymErrLo(0), _asymErrHi(0), _binning(new RooUniformBinning())
{
  _fast = true ;
  TRACE_CREATE;
}
 
 
////////////////////////////////////////////////////////////////////////////////
/// Create a constant variable with a value and optional unit.
RooRealVar::RooRealVar(const char *name, const char *title,
             double value, const char *unit) :
  RooAbsRealLValue(name, title, unit), _error(-1), _asymErrLo(1), _asymErrHi(-1),
  _binning(new RooUniformBinning(-1,1,100))
{
  _value = value ;
  _fast = true ;
  removeRange();
  setConstant(true) ;
  TRACE_CREATE;
}
 
 
////////////////////////////////////////////////////////////////////////////////
/// Create a variable allowed to float in the given range.
/// The initial value will be set to the center of the range.
RooRealVar::RooRealVar(const char *name, const char *title,
             double minValue, double maxValue,
             const char *unit) :
  RooAbsRealLValue(name, title, unit), _error(-1), _asymErrLo(1), _asymErrHi(-1),
  _binning(new RooUniformBinning(minValue,maxValue,100))
{
  _fast = true ;
 
  if (RooNumber::isInfinite(minValue)) {
    if (RooNumber::isInfinite(maxValue)) {
      // [-inf,inf]
      _value = 0 ;
    } else {
      // [-inf,X]
      _value= maxValue ;
    }
  } else {
    if (RooNumber::isInfinite(maxValue)) {
      // [X,inf]
      _value = minValue ;
    } else {
      // [X,X]
      _value= 0.5*(minValue + maxValue);
    }
  }
 
  //   setPlotRange(minValue,maxValue) ;
  setRange(minValue,maxValue) ;
  TRACE_CREATE;
}
 
 
////////////////////////////////////////////////////////////////////////////////
/// Create a variable with the given starting value. It is allowed to float
/// within the defined range. Optionally, a unit can be specified for axis labels.
RooRealVar::RooRealVar(const char *name, const char *title,
             double value, double minValue, double maxValue,
             const char *unit) :
  RooAbsRealLValue(name, title, unit), _error(-1), _asymErrLo(1), _asymErrHi(-1),
  _binning(new RooUniformBinning(minValue,maxValue,100))
{
    _fast = true ;
    setRange(minValue,maxValue) ;
 
    double clipValue ;
    inRange(value,nullptr,&clipValue) ;
    _value = clipValue ;
 
    TRACE_CREATE;
}
 
 
////////////////////////////////////////////////////////////////////////////////
/// Copy Constructor
 
RooRealVar::RooRealVar(const RooRealVar& other, const char* name) :
  RooAbsRealLValue(other,name),
  _error(other._error),
  _asymErrLo(other._asymErrLo),
  _asymErrHi(other._asymErrHi)
{
  _sharedProp = other.sharedProp();
  if (other._binning) {
     _binning.reset(other._binning->clone());
     _binning->insertHook(*this) ;
  }
  _fast = true ;
 
  for (const auto& item : other._altNonSharedBinning) {
    std::unique_ptr<RooAbsBinning> abc( item.second->clone() );
    abc->insertHook(*this) ;
    _altNonSharedBinning[item.first] = std::move(abc);
  }
 
  TRACE_CREATE;
 
}
 
 
////////////////////////////////////////////////////////////////////////////////
/// Destructor
 
RooRealVar::~RooRealVar()
{
  // We should not forget to explicitly call deleteSharedProperties() in the
  // destructor, because this is where the expired weak_ptrs in the
  // _sharedPropList get erased.
  deleteSharedProperties();
 
  TRACE_DESTROY;
}
 
 
////////////////////////////////////////////////////////////////////////////////
/// Return value of variable
 
double RooRealVar::getValV(const RooArgSet*) const
{
  return _value ;
}
 
 
////////////////////////////////////////////////////////////////////////////////
/// Set value of variable to 'value'. If 'value' is outside
/// range of object, clip value into range
 
void RooRealVar::setVal(double value)
{
  double clipValue ;
  inRange(value,nullptr,&clipValue) ;
 
  if (clipValue != _value) {
    setValueDirty() ;
    _value = clipValue;
    ++_valueResetCounter;
  }
}
 
 
 
////////////////////////////////////////////////////////////////////////////////
/// Set value of variable to `value`. If `value` is outside of the
/// range named `rangeName`, clip value into that range.
void RooRealVar::setVal(double value, const char* rangeName)
{
  double clipValue ;
  inRange(value,rangeName,&clipValue) ;
 
  if (clipValue != _value) {
    setValueDirty() ;
    _value = clipValue;
    ++_valueResetCounter;
  }
}
 
 
 
////////////////////////////////////////////////////////////////////////////////
/// Return a RooAbsRealLValue representing the error associated
/// with this variable. The callers takes ownership of the
/// return object
 
RooErrorVar* RooRealVar::errorVar() const
{
  TString name(GetName());
  TString title(GetTitle());
  name.Append("err") ;
  title.Append(" Error") ;
 
  return new RooErrorVar(name,title,*this) ;
}
 
 
 
////////////////////////////////////////////////////////////////////////////////
/// Returns true if variable has a binning named 'name'.
 
bool RooRealVar::hasBinning(const char* name) const
{
  return sharedProp()->_altBinning.find(name) != sharedProp()->_altBinning.end();
}
 
 
 
////////////////////////////////////////////////////////////////////////////////
/// Return binning definition with name. If binning with 'name' is not found it is created
/// on the fly as a clone of the default binning if createOnTheFly is true, otherwise
/// a reference to the default binning is returned. If verbose is true a message
/// is printed if a binning is created on the fly.
 
const RooAbsBinning& RooRealVar::getBinning(const char* name, bool verbose, bool createOnTheFly) const
{
  return const_cast<RooRealVar*>(this)->getBinning(name, verbose, createOnTheFly) ;
}
 
 
 
////////////////////////////////////////////////////////////////////////////////
/// Return binning definition with name. If binning with 'name' is not found it is created
/// on the fly as a clone of the default binning if createOnTheFly is true, otherwise
/// a reference to the default binning is returned. If verbose is true a message
/// is printed if a binning is created on the fly.
 
RooAbsBinning& RooRealVar::getBinning(const char* name, bool verbose, bool createOnTheFly)
{
  // Return default (normalization) binning and range if no name is specified
  if (name==nullptr) {
    return *_binning ;
  }
 
  if (strchr(name, ',')) {
    coutW(InputArguments) << "Asking variable " << GetName() << "for binning '" << name
        << "', but comma in binning names is not supported." << std::endl;
  }
 
  // Check if non-shared binning with this name has been created already
  auto item = _altNonSharedBinning.find(name);
  if (item != _altNonSharedBinning.end()) {
    return *item->second;
  }
 
  // Check if binning with this name has been created already
  auto item2 = sharedProp()->_altBinning.find(name);
  if (item2 != sharedProp()->_altBinning.end()) {
    return *item2->second;
  }
 
 
  // Return default binning if requested binning doesn't exist
  if (!createOnTheFly) {
    return *_binning ;
  }
 
  // Create a new RooRangeBinning with this name with default range
  auto binning = new RooRangeBinning(getMin(),getMax(),name) ;
  if (verbose) {
    coutI(Eval) << "RooRealVar::getBinning(" << GetName() << ") new range named '"
      << name << "' created with default bounds" << std::endl ;
  }
  sharedProp()->_altBinning[name] = binning;
 
  return *binning ;
}
 
////////////////////////////////////////////////////////////////////////////////
/// Get a list of all binning names. An empty name implies the default binning and
/// a nullptr pointer should be passed to getBinning in this case.
 
std::list<std::string> RooRealVar::getBinningNames() const
{
  std::list<std::string> binningNames;
  if (_binning) {
    binningNames.push_back("");
  }
 
  for (const auto& item : _altNonSharedBinning) {
    binningNames.push_back(item.first);
  }
  for (const auto& item : sharedProp()->_altBinning) {
    binningNames.push_back(item.first);
  }
 
  return binningNames;
}
 
void RooRealVar::removeMin(const char* name) {
  getBinning(name).setMin(-RooNumber::infinity());
}
void RooRealVar::removeMax(const char* name) {
  getBinning(name).setMax(RooNumber::infinity());
}
void RooRealVar::removeRange(const char* name) {
  getBinning(name).setRange(-RooNumber::infinity(),RooNumber::infinity());
}
 
 
////////////////////////////////////////////////////////////////////////////////
/// Create a uniform binning under name 'name' for this variable.
/// \param[in] nBins Number of bins. The limits are taken from the currently set limits.
/// \param[in] name Optional name. If name is null, install as default binning.
void RooRealVar::setBins(Int_t nBins, const char* name) {
  setBinning(RooUniformBinning(getMin(name),getMax(name),nBins),name);
}
 
////////////////////////////////////////////////////////////////////////////////
/// Add given binning under name 'name' with this variable. If name is null,
/// the binning is installed as the default binning.
void RooRealVar::setBinning(const RooAbsBinning& binning, const char* name)
{
  std::unique_ptr<RooAbsBinning> newBinning( binning.clone() );
 
  // Process insert hooks required for parameterized binnings
  if (!name || name[0] == 0) {
    if (_binning) {
      _binning->removeHook(*this) ;
    }
    newBinning->insertHook(*this) ;
    _binning = std::move(newBinning);
  } else {
    // Remove any old binning with this name
    auto sharedProps = sharedProp();
    auto item = sharedProps->_altBinning.find(name);
    if (item != sharedProps->_altBinning.end()) {
      item->second->removeHook(*this);
      if (sharedProps->_ownBinnings)
        delete item->second;
 
      sharedProps->_altBinning.erase(item);
    }
    auto item2 = _altNonSharedBinning.find(name);
    if (item2 != _altNonSharedBinning.end()) {
      item2->second->removeHook(*this);
      _altNonSharedBinning.erase(item2);
    }
 
    // Install new
    newBinning->SetName(name) ;
    newBinning->SetTitle(name) ;
    newBinning->insertHook(*this) ;
    if (newBinning->isShareable()) {
      sharedProp()->_altBinning[name] = newBinning.release();
    } else {
      _altNonSharedBinning[name] = std::move(newBinning);
    }
  }
}
 
 
 
////////////////////////////////////////////////////////////////////////////////
/// Set minimum of name range to given value. If name is null
/// minimum of default range is set
 
void RooRealVar::setMin(const char* name, double value)
{
  // Set new minimum of fit range
  RooAbsBinning& binning = getBinning(name,true,true) ;
 
  // Check if new limit is consistent
  if (value >= getMax()) {
    coutW(InputArguments) << "RooRealVar::setMin(" << GetName()
           << "): Proposed new fit min. larger than max., setting min. to max." << std::endl ;
    binning.setMin(getMax()) ;
  } else {
    binning.setMin(value) ;
  }
 
  // Clip current value in window if it fell out
  if (!name) {
    double clipValue ;
    if (!inRange(_value,nullptr,&clipValue)) {
      setVal(clipValue) ;
    }
  }
 
  setShapeDirty() ;
}
 
 
////////////////////////////////////////////////////////////////////////////////
/// Set maximum of name range to given value. If name is null
/// maximum of default range is set
 
void RooRealVar::setMax(const char* name, double value)
{
  // Set new maximum of fit range
  RooAbsBinning& binning = getBinning(name,true,true) ;
 
  // Check if new limit is consistent
  if (value < getMin()) {
    coutW(InputArguments) << "RooRealVar::setMax(" << GetName()
           << "): Proposed new fit max. smaller than min., setting max. to min." << std::endl ;
    binning.setMax(getMin()) ;
  } else {
    binning.setMax(value) ;
  }
 
  // Clip current value in window if it fell out
  if (!name) {
    double clipValue ;
    if (!inRange(_value,nullptr,&clipValue)) {
      setVal(clipValue) ;
    }
  }
 
  setShapeDirty() ;
}
 
 
////////////////////////////////////////////////////////////////////////////////
/// Set a fit or plotting range.
/// Ranges can be selected for e.g. fitting, plotting or integration. Note that multiple
/// variables can have ranges with the same name, so multi-dimensional PDFs can be sliced.
/// See also the tutorial rf203_ranges.C
/// \param[in] name Name this range (so it can be selected later for fitting or
/// plotting). If the name is `nullptr`, the function sets the limits of the default range.
/// \param[in] min Miniminum of the range.
/// \param[in] max Maximum of the range.
void RooRealVar::setRange(const char* name, double min, double max)
{
  bool exists = name == nullptr || sharedProp()->_altBinning.count(name) > 0;
 
  // Set new fit range
  RooAbsBinning& binning = getBinning(name,false,true) ;
 
  // Check if new limit is consistent
  if (min>max) {
    coutW(InputArguments) << "RooRealVar::setRange(" << GetName()
           << "): Proposed new fit max. smaller than min., setting max. to min." << std::endl ;
    binning.setRange(min,min) ;
  } else {
    binning.setRange(min,max) ;
  }
 
  if (!exists) {
    coutI(Eval) << "RooRealVar::setRange(" << GetName()
      << ") new range named '" << name << "' created with bounds ["
      << min << "," << max << "]" << std::endl ;
  }
 
  setShapeDirty() ;
}
 
 
 
////////////////////////////////////////////////////////////////////////////////
/// Set or modify a parameterised range, i.e., a range the varies in dependence
/// of parameters.
/// See setRange() for more details.
void RooRealVar::setRange(const char* name, RooAbsReal& min, RooAbsReal& max)
{
  RooParamBinning pb(min,max,100) ;
  setBinning(pb,name) ;
}
 
 
 
////////////////////////////////////////////////////////////////////////////////
/// Read object contents from given stream
 
bool RooRealVar::readFromStream(istream& is, bool compact, bool verbose)
{
  TString token;
  TString errorPrefix("RooRealVar::readFromStream(");
  errorPrefix.Append(GetName()) ;
  errorPrefix.Append(")") ;
  RooStreamParser parser(is,errorPrefix) ;
  double value(0) ;
 
  if (compact) {
    // Compact mode: Read single token
    if (parser.readDouble(value,verbose)) return true ;
    if (isValidReal(value,verbose)) {
      setVal(value) ;
      return false ;
    } else {
      return true ;
    }
 
  } else {
    // Extended mode: Read multiple tokens on a single line
    bool haveValue(false) ;
    bool haveConstant(false) ;
    removeError() ;
    removeAsymError() ;
 
    bool reprocessToken = false ;
    while(true) {
      if (parser.atEOL() || parser.atEOF()) break ;
 
      if (!reprocessToken) {
   token=parser.readToken() ;
      }
      reprocessToken = false ;
 
      if (!token.CompareTo("+")) {
 
   // Expect +/- as 3-token sequence
   if (parser.expectToken("/",true) ||
       parser.expectToken("-",true)) {
     break ;
   }
 
   // Next token is error or asymmetric error, check if first char of token is a '('
   TString tmp = parser.readToken() ;
   if (tmp.CompareTo("(")) {
     // Symmetric error, convert token do double
 
     double error ;
     parser.convertToDouble(tmp,error) ;
     setError(error) ;
 
   } else {
     // Have error
     double asymErrLo = 0.;
     double asymErrHi = 0.;
     if (parser.readDouble(asymErrLo,true) ||
         parser.expectToken(",",true) ||
         parser.readDouble(asymErrHi,true) ||
         parser.expectToken(")",true)) break ;
     setAsymError(asymErrLo,asymErrHi) ;
   }
 
      } else if (!token.CompareTo("C")) {
 
   // Set constant
   setConstant(true) ;
   haveConstant = true ;
 
      } else if (!token.CompareTo("P")) {
 
   // Next tokens are plot limits
   double plotMin(0);
   double plotMax(0);
   Int_t plotBins(0);
   if (parser.expectToken("(",true) ||
       parser.readDouble(plotMin,true) ||
       parser.expectToken("-",true) ||
       parser.readDouble(plotMax,true) ||
            parser.expectToken(":",true) ||
            parser.readInteger(plotBins,true) ||
       parser.expectToken(")",true)) break ;
//    setPlotRange(plotMin,plotMax) ;
   coutW(Eval) << "RooRealVar::readFromStream(" << GetName()
        << ") WARNING: plot range deprecated, removed P(...) token" << std::endl ;
 
      } else if (!token.CompareTo("F")) {
 
   // Next tokens are fit limits
   double fitMin;
   double fitMax;
   Int_t fitBins ;
   if (parser.expectToken("(",true) ||
       parser.readDouble(fitMin,true) ||
       parser.expectToken("-",true) ||
       parser.readDouble(fitMax,true) ||
       parser.expectToken(":",true) ||
       parser.readInteger(fitBins,true) ||
       parser.expectToken(")",true)) break ;
   //setBins(fitBins) ;
   //setRange(fitMin,fitMax) ;
   coutW(Eval) << "RooRealVar::readFromStream(" << GetName()
        << ") WARNING: F(lo-hi:bins) token deprecated, use L(lo-hi) B(bins)" << std::endl ;
   if (!haveConstant) setConstant(false) ;
 
      } else if (!token.CompareTo("L")) {
 
   // Next tokens are fit limits
   double fitMin = 0.0;
   double fitMax = 0.0;
   // Int_t fitBins ;
   if (parser.expectToken("(",true) ||
       parser.readDouble(fitMin,true) ||
       parser.expectToken("-",true) ||
       parser.readDouble(fitMax,true) ||
       parser.expectToken(")",true)) break ;
   setRange(fitMin,fitMax) ;
   if (!haveConstant) setConstant(false) ;
 
      } else if (!token.CompareTo("B")) {
 
   // Next tokens are fit limits
   Int_t fitBins = 0;
   if (parser.expectToken("(",true) ||
       parser.readInteger(fitBins,true) ||
       parser.expectToken(")",true)) break ;
   setBins(fitBins) ;
 
      } else {
   // Token is value
   if (parser.convertToDouble(token,value)) { parser.zapToEnd() ; break ; }
   haveValue = true ;
   // Defer value assignment to end
      }
    }
    if (haveValue) setVal(value) ;
    return false ;
  }
}
 
 
////////////////////////////////////////////////////////////////////////////////
/// Write object contents to given stream
 
void RooRealVar::writeToStream(ostream& os, bool compact) const
{
  if (compact) {
    // Write value only
    os << getVal() ;
  } else {
 
    // Write value with error (if not zero)
    if (_printScientific) {
      char fmtVal[16];
      char fmtErr[16];
      snprintf(fmtVal,16,"%%.%de",_printSigDigits) ;
      snprintf(fmtErr,16,"%%.%de",(_printSigDigits+1)/2) ;
      if (_value>=0) os << " " ;
      os << Form(fmtVal,_value) ;
 
      if (hasAsymError()) {
   os << " +/- (" << Form(fmtErr,getAsymErrorLo())
      << ", " << Form(fmtErr,getAsymErrorHi()) << ")" ;
      } else  if (hasError()) {
   os << " +/- " << Form(fmtErr,getError()) ;
      }
 
      os << " " ;
    } else {
      os << format(_printSigDigits,"EFA") << " " ;
    }
 
    // Append limits if not constants
    if (isConstant()) {
      os << "C " ;
    }
 
    // Append fit limits
    os << "L(" ;
    if(hasMin()) {
      os << getMin();
    }
    else {
      os << "-INF";
    }
    if(hasMax()) {
      os << " - " << getMax() ;
    }
    else {
      os << " - +INF";
    }
    os << ") " ;
 
    if (getBins()!=100) {
      os << "B(" << getBins() << ") " ;
    }
 
    // Add comment with unit, if unit exists
    if (!_unit.IsNull())
      os << "// [" << getUnit() << "]" ;
  }
}
 
 
 
////////////////////////////////////////////////////////////////////////////////
/// Print value of variable
 
void RooRealVar::printValue(ostream& os) const
{
  os << getVal() ;
 
  if(hasError() && !hasAsymError()) {
    os << " +/- " << getError() ;
  } else if (hasAsymError()) {
    os << " +/- (" << getAsymErrorLo() << "," << getAsymErrorHi() << ")" ;
  }
 
}
 
 
////////////////////////////////////////////////////////////////////////////////
/// Print extras of variable: (asymmetric) error, constant flag, limits and binning
 
void RooRealVar::printExtras(ostream& os) const
{
  // Append limits if not constants
  if (isConstant()) {
    os << "C " ;
  }
 
  // Append fit limits
  os << " L(" ;
  if(hasMin()) {
    os << getMin();
  }
  else {
    os << "-INF";
  }
  if(hasMax()) {
    os << " - " << getMax() ;
  }
  else {
    os << " - +INF";
  }
  os << ") " ;
 
  if (getBins()!=100) {
    os << "B(" << getBins() << ") " ;
  }
 
  // Add comment with unit, if unit exists
  if (!_unit.IsNull())
    os << "// [" << getUnit() << "]" ;
 
//   std::cout << " _value = " << &_value << " _error = " << &_error ;
 
 
}
 
 
////////////////////////////////////////////////////////////////////////////////
/// Mapping of Print() option string to RooPrintable contents specifications
 
Int_t RooRealVar::defaultPrintContents(Option_t* opt) const
{
  if (opt && TString(opt)=="I") {
    return kName|kClassName|kValue ;
  }
  return kName|kClassName|kValue|kExtras ;
}
 
 
////////////////////////////////////////////////////////////////////////////////
/// Detailed printing interface
 
void RooRealVar::printMultiline(ostream& os, Int_t contents, bool verbose, TString indent) const
{
  RooAbsRealLValue::printMultiline(os,contents,verbose,indent);
  os << indent << "--- RooRealVar ---" << std::endl;
  TString unit(_unit);
  if(!unit.IsNull()) unit.Prepend(' ');
  os << indent << "  Error = " << getError() << unit << std::endl;
}
 
 
 
////////////////////////////////////////////////////////////////////////////////
/// Format contents of RooRealVar for pretty printing on RooPlot
/// parameter boxes. This function processes the named arguments
/// taken by paramOn() and translates them to an option string
/// parsed by RooRealVar::format(Int_t sigDigits, const char *options)
 
std::string RooRealVar::format(const RooCmdArg& formatArg) const
{
  RooCmdArg tmp(formatArg) ;
  tmp.setProcessRecArgs(true) ;
 
  RooCmdConfig pc("RooRealVar::format(" + std::string(GetName()) + ")");
  pc.defineString("what","FormatArgs",0,"") ;
  pc.defineInt("autop","FormatArgs::AutoPrecision",0,2) ;
  pc.defineInt("fixedp","FormatArgs::FixedPrecision",0,2) ;
  pc.defineInt("tlatex","FormatArgs::TLatexStyle",0,0) ;
  pc.defineInt("latex","FormatArgs::LatexStyle",0,0) ;
  pc.defineInt("latext","FormatArgs::LatexTableStyle",0,0) ;
  pc.defineInt("verbn","FormatArgs::VerbatimName",0,0) ;
  pc.defineMutex("FormatArgs::TLatexStyle","FormatArgs::LatexStyle","FormatArgs::LatexTableStyle") ;
  pc.defineMutex("FormatArgs::AutoPrecision","FormatArgs::FixedPrecision") ;
 
  // Process & check varargs
  pc.process(tmp) ;
  if (!pc.ok(true)) {
    return "";
  }
 
  // Extract values from named arguments
  TString options ;
  options = pc.getString("what") ;
 
  if (pc.getInt("tlatex")) {
    options += "L" ;
  } else if (pc.getInt("latex")) {
    options += "X" ;
  } else if (pc.getInt("latext")) {
    options += "Y" ;
  }
 
  if (pc.getInt("verbn")) options += "V" ;
  Int_t sigDigits = 2 ;
  if (pc.hasProcessed("FormatArgs::AutoPrecision")) {
    options += "P" ;
    sigDigits = pc.getInt("autop") ;
  } else if (pc.hasProcessed("FormatArgs::FixedPrecision")) {
    options += "F" ;
    sigDigits = pc.getInt("fixedp") ;
  }
 
  return format(sigDigits,options) ;
}
 
 
 
 
////////////////////////////////////////////////////////////////////////////////
/// Format numeric value of RooRealVar and its error in a variety of ways
///
/// To control what is shown use the following options
/// N = show name
/// T = show title (takes precedent over `N`, falls back to `N` if title is empty)
/// H = hide value
/// E = show error
/// A = show asymmetric error instead of parabolic error (if available)
/// U = show unit
///
/// To control how it is shown use these options
/// L = TLatex mode
/// X = Latex mode
/// Y = Latex table mode ( '=' replaced by '&' )
/// V = Make name \\verbatim in Latex mode
/// P = use error to control shown precision
/// F = force fixed precision
///
 
std::string RooRealVar::format(Int_t sigDigits, const char *options) const
{
  // parse the options string
  TString opts(options);
  opts.ToLower();
 
  bool showName= opts.Contains("n");
  bool showTitle = opts.Contains("t");
  bool hideValue= opts.Contains("h");
  bool showError= opts.Contains("e");
  bool showUnit= opts.Contains("u");
  bool tlatexMode= opts.Contains("l");
  bool latexMode= opts.Contains("x");
  bool latexTableMode = opts.Contains("y") ;
  bool latexVerbatimName = opts.Contains("v") ;
 
  std::string label = showName ? getPlotLabel() : "";
  if(showTitle) {
     label = GetTitle();
     if(label.empty()) label = getPlotLabel();
  }
 
  if (latexTableMode) latexMode = true ;
  bool asymError= opts.Contains("a") ;
  bool useErrorForPrecision= (((showError && hasError(false) && !isConstant()) || opts.Contains("p")) && !opts.Contains("f")) ;
  // calculate the precision to use
  if(sigDigits < 1) sigDigits= 1;
  Int_t leadingDigitVal = 0;
  if (useErrorForPrecision) {
    leadingDigitVal = (Int_t)floor(log10(std::abs(_error+1e-10)));
    if (_value==0&&_error==0) leadingDigitVal=0 ;
  } else {
    leadingDigitVal = (Int_t)floor(log10(std::abs(_value+1e-10)));
    if (_value==0) leadingDigitVal=0 ;
  }
  Int_t leadingDigitErr= (Int_t)floor(log10(std::abs(_error+1e-10)));
  Int_t whereVal= leadingDigitVal - sigDigits + 1;
  Int_t whereErr= leadingDigitErr - sigDigits + 1;
  char fmtVal[16];
  char fmtErr[16];
 
  if (_value<0) whereVal -= 1 ;
  snprintf(fmtVal,16,"%%.%df", whereVal < 0 ? -whereVal : 0);
  snprintf(fmtErr,16,"%%.%df", whereErr < 0 ? -whereErr : 0);
  std::string text;
  if(latexMode) text += "$";
  // begin the string with "<name> = " if requested
  if(showName || showTitle) {
    if (latexTableMode && latexVerbatimName) {
      text += "\\verb+";
    }
    text += label;
    if (latexVerbatimName) text += "+";
 
    if (!latexTableMode) {
      text += " = ";
    } else {
      text += " $ & $ ";
    }
  }
 
  // Add leading space if value is positive
  if (_value>=0) text += " ";
 
  // append our value if requested
  char buffer[256];
  if(!hideValue) {
    chopAt(_value, whereVal);
    snprintf(buffer, 256,fmtVal, _value);
    text += buffer;
  }
 
  // append our error if requested and this variable is not constant
  if(hasError(false) && showError && !(asymError && hasAsymError(false))) {
    if(tlatexMode) {
      text += " #pm ";
    }
    else {
      text += latexMode ? "\\pm " : " +/- ";
    }
    snprintf(buffer, 256,fmtErr, getError());
    text += buffer;
  }
 
  if (asymError && hasAsymError() && showError) {
    if(tlatexMode) {
      text += " #pm _{";
      snprintf(buffer, 256,fmtErr, getAsymErrorLo());
      text += buffer;
      text += "}^{+";
      snprintf(buffer, 256,fmtErr, getAsymErrorHi());
      text += buffer;
      text += "}";
    }
    else if(latexMode) {
      text += "\\pm _{";
      snprintf(buffer, 256,fmtErr, getAsymErrorLo());
      text += buffer;
      text += "}^{+";
      snprintf(buffer, 256,fmtErr, getAsymErrorHi());
      text += buffer;
      text += "}";
    }
    else {
      text += " +/-  (";
      snprintf(buffer, 256, fmtErr, getAsymErrorLo());
      text += buffer;
      text += ", ";
      snprintf(buffer, 256, fmtErr, getAsymErrorHi());
      text += buffer;
      text += ")";
    }
 
  }
 
  // append our units if requested
  if(!_unit.IsNull() && showUnit) {
    text += ' ';
    text += _unit;
  }
  if(latexMode) text += "$";
  return text;
}
 
 
 
////////////////////////////////////////////////////////////////////////////////
/// Utility to calculate number of decimals to show
/// based on magnitude of error
 
double RooRealVar::chopAt(double what, Int_t where) const
{
  double scale= pow(10.0,where);
  Int_t trunc= (Int_t)floor(what/scale + 0.5);
  return (double)trunc*scale;
}
 
 
 
////////////////////////////////////////////////////////////////////////////////
/// Overload RooAbsReal::attachToTree to also attach
/// branches for errors  and/or asymmetric errors
/// attribute StoreError and/or StoreAsymError are set
 
void RooRealVar::attachToVStore(RooVectorDataStore& vstore)
{
  // Follow usual procedure for value
 
  if (getAttribute("StoreError") || getAttribute("StoreAsymError") || vstore.isFullReal(this) ) {
 
    RooVectorDataStore::RealFullVector* rfv = vstore.addRealFull(this) ;
    rfv->setBuffer(this,&_value);
 
    // Attach/create additional branch for error
    if (getAttribute("StoreError") || vstore.hasError(this) ) {
      rfv->setErrorBuffer(&_error) ;
    }
 
    // Attach/create additional branches for asymmetric error
    if (getAttribute("StoreAsymError") || vstore.hasAsymError(this)) {
      rfv->setAsymErrorBuffer(&_asymErrLo,&_asymErrHi) ;
    }
 
  } else {
 
    RooAbsReal::attachToVStore(vstore) ;
 
  }
}
 
 
 
////////////////////////////////////////////////////////////////////////////////
/// Overload RooAbsReal::attachToTree to also attach
/// branches for errors  and/or asymmetric errors
/// attribute StoreError and/or StoreAsymError are set
 
void RooRealVar::attachToTree(TTree& t, Int_t bufSize)
{
  // Follow usual procedure for value
  RooAbsReal::attachToTree(t,bufSize) ;
//   std::cout << "RooRealVar::attachToTree(" << this << ") name = " << GetName()
//        << " StoreError = " << (getAttribute("StoreError")?"T":"F") << std::endl ;
 
  // Attach/create additional branch for error
  if (getAttribute("StoreError")) {
    TString errName(GetName()) ;
    errName.Append("_err") ;
    TBranch* branch = t.GetBranch(errName) ;
    if (branch) {
      t.SetBranchAddress(errName,&_error) ;
    } else {
      TString format2(errName);
      format2.Append("/D");
      t.Branch(errName, &_error, (const Text_t*)format2, bufSize);
    }
  }
 
  // Attach/create additional branches for asymmetric error
  if (getAttribute("StoreAsymError")) {
    TString loName(GetName()) ;
    loName.Append("_aerr_lo") ;
    TBranch* lobranch = t.GetBranch(loName) ;
    if (lobranch) {
      t.SetBranchAddress(loName,&_asymErrLo) ;
    } else {
      TString format2(loName);
      format2.Append("/D");
      t.Branch(loName, &_asymErrLo, (const Text_t*)format2, bufSize);
    }
 
    TString hiName(GetName()) ;
    hiName.Append("_aerr_hi") ;
    TBranch* hibranch = t.GetBranch(hiName) ;
    if (hibranch) {
      t.SetBranchAddress(hiName,&_asymErrHi) ;
    } else {
      TString format2(hiName);
      format2.Append("/D");
      t.Branch(hiName, &_asymErrHi, (const Text_t*)format2, bufSize);
    }
  }
}
 
 
////////////////////////////////////////////////////////////////////////////////
/// Overload RooAbsReal::fillTreeBranch to also
/// fill tree branches with (asymmetric) errors
/// if requested.
 
void RooRealVar::fillTreeBranch(TTree& t)
{
  // First determine if branch is taken
  TString cleanName(cleanBranchName()) ;
  TBranch* valBranch = t.GetBranch(cleanName) ;
  if (!valBranch) {
    coutE(Eval) << "RooAbsReal::fillTreeBranch(" << GetName() << ") ERROR: not attached to tree" << std::endl ;
    assert(0) ;
  }
  valBranch->Fill() ;
 
  if (getAttribute("StoreError")) {
    TString errName(GetName()) ;
    errName.Append("_err") ;
    TBranch* errBranch = t.GetBranch(errName) ;
    if (errBranch) errBranch->Fill() ;
  }
 
  if (getAttribute("StoreAsymError")) {
    TString loName(GetName()) ;
    loName.Append("_aerr_lo") ;
    TBranch* loBranch = t.GetBranch(loName) ;
    if (loBranch) loBranch->Fill() ;
 
    TString hiName(GetName()) ;
    hiName.Append("_aerr_hi") ;
    TBranch* hiBranch = t.GetBranch(hiName) ;
    if (hiBranch) hiBranch->Fill() ;
  }
}
 
 
 
////////////////////////////////////////////////////////////////////////////////
/// Copy the cached value of another RooAbsArg to our cache
/// Warning: This function copies the cached values of source,
///          it is the callers responsibility to make sure the cache is clean
 
void RooRealVar::copyCache(const RooAbsArg* source, bool valueOnly, bool setValDirty)
{
  // Follow usual procedure for valueklog
  double oldVal = _value;
  RooAbsReal::copyCache(source,valueOnly,setValDirty) ;
  if(_value != oldVal) {
    ++_valueResetCounter;
  }
 
  if (valueOnly) return ;
 
  // Copy error too, if source has one
  RooRealVar* other = dynamic_cast<RooRealVar*>(const_cast<RooAbsArg*>(source)) ;
  if (other) {
    // Copy additional error value
    _error = other->_error ;
    _asymErrLo = other->_asymErrLo ;
    _asymErrHi = other->_asymErrHi ;
  }
}
 
 
 
////////////////////////////////////////////////////////////////////////////////
/// Stream an object of class RooRealVar.
 
void RooRealVar::Streamer(TBuffer &R__b)
{
  UInt_t R__s;
  UInt_t R__c;
  if (R__b.IsReading()) {
 
    Version_t R__v = R__b.ReadVersion(&R__s, &R__c); if (R__v) { }
    RooAbsRealLValue::Streamer(R__b);
    if (R__v==1) {
      coutI(Eval) << "RooRealVar::Streamer(" << GetName() << ") converting version 1 data format" << std::endl ;
      double fitMin;
      double fitMax;
      Int_t fitBins ;
      R__b >> fitMin;
      R__b >> fitMax;
      R__b >> fitBins;
      _binning = std::make_unique<RooUniformBinning>(fitMin,fitMax,fitBins);
    }
    R__b >> _error;
    R__b >> _asymErrLo;
    R__b >> _asymErrHi;
    if (R__v>=2) {
      RooAbsBinning* binning;
      R__b >> binning;
      _binning.reset(binning);
    }
    if (R__v==3) {
      // In v3, properties were written as pointers, so read now and install:
      RooRealVarSharedProperties* tmpProp;
      R__b >> tmpProp;
      installSharedProp(std::shared_ptr<RooRealVarSharedProperties>(tmpProp));
    }
    if (R__v>=4) {
      // In >= v4, properties were written directly, but they might be the "_nullProp"
      auto tmpProp = std::make_shared<RooRealVarSharedProperties>();
      tmpProp->Streamer(R__b);
      installSharedProp(std::move(tmpProp));
    }
 
    R__b.CheckByteCount(R__s, R__c, RooRealVar::IsA());
 
  } else {
 
    R__c = R__b.WriteVersion(RooRealVar::IsA(), true);
    RooAbsRealLValue::Streamer(R__b);
    R__b << _error;
    R__b << _asymErrLo;
    R__b << _asymErrHi;
    R__b << _binning.get();
    if (_sharedProp) {
      _sharedProp->Streamer(R__b) ;
    } else {
      _nullProp().Streamer(R__b) ;
    }
    R__b.SetByteCount(R__c, true);
 
  }
}
 
/// Hand out our shared property, create on the fly and register
/// in shared map if necessary.
std::shared_ptr<RooRealVarSharedProperties> RooRealVar::sharedProp() const {
  if (!_sharedProp) {
    const_cast<RooRealVar*>(this)->installSharedProp(std::make_shared<RooRealVarSharedProperties>());
  }
 
  return _sharedProp;
}
 
 
////////////////////////////////////////////////////////////////////////////////
/// Install the shared property into the member _sharedProp.
/// If a property with same name already exists, discard the incoming one,
/// and share the existing.
/// `nullptr` and properties equal to the RooRealVar::_nullProp will not be installed.
void RooRealVar::installSharedProp(std::shared_ptr<RooRealVarSharedProperties>&& prop) {
  if (prop == nullptr || (*prop == _nullProp())) {
    _sharedProp = nullptr;
    return;
  }
 
 
  auto& weakPtr = (*sharedPropList())[prop->uuid()];
  std::shared_ptr<RooRealVarSharedProperties> existingProp;
  if ( (existingProp = weakPtr.lock()) ) {
    // Property exists, discard incoming
    _sharedProp = std::move(existingProp);
    // Incoming is not allowed to delete the binnings now - they are owned by the other instance
    prop->disownBinnings();
  } else {
    // Doesn't exist. Install, register weak pointer for future sharing
    _sharedProp = std::move(prop);
    weakPtr = _sharedProp;
  }
}
 
 
////////////////////////////////////////////////////////////////////////////////
/// Stop sharing properties.
void RooRealVar::deleteSharedProperties()
{
  // Nothing to do if there were no shared properties to begin with.
  if(!_sharedProp) return;
 
  // Get the key for the _sharedPropList.
  auto key = _sharedProp->uuid(); // we have to make a copy because _sharedPropList gets delete next.
 
  // Actually delete the shared properties object.
  _sharedProp.reset();
 
  // If the _sharedPropList was already deleted, we can return now.
  if(!sharedPropList()) return;
 
  // Find the std::weak_ptr that the _sharedPropList holds to our
  // _sharedProp.
  auto iter = sharedPropList()->find(key);
 
  // If no other RooRealVars shared the shared properties with us, the
  // weak_ptr in _sharedPropList is expired and we can erase it from the map.
  if(iter->second.expired()) {
    sharedPropList()->erase(iter);
  }
}
 
 
////////////////////////////////////////////////////////////////////////////////
/// If true, contents of RooRealVars will be printed in scientific notation
 
void RooRealVar::printScientific(bool flag)
{
  _printScientific = flag ;
}
 
 
////////////////////////////////////////////////////////////////////////////////
/// Set number of digits to show when printing RooRealVars
 
void RooRealVar::printSigDigits(Int_t ndig)
{
  _printSigDigits = ndig>1?ndig:1 ;
}