diff --git a/src/Core/AnalysisHandler.cc b/src/Core/AnalysisHandler.cc
--- a/src/Core/AnalysisHandler.cc
+++ b/src/Core/AnalysisHandler.cc
@@ -1,689 +1,689 @@
 // -*- C++ -*-
 #include "Rivet/Config/RivetCommon.hh"
 #include "Rivet/AnalysisHandler.hh"
 #include "Rivet/Analysis.hh"
 #include "Rivet/Tools/ParticleName.hh"
 #include "Rivet/Tools/BeamConstraint.hh"
 #include "Rivet/Tools/Logging.hh"
 #include "Rivet/Projections/Beam.hh"
 #include "YODA/IO.h"
 #include <iostream>
 
 using std::cout;
 using std::cerr;
 
 namespace Rivet {
 
 
   AnalysisHandler::AnalysisHandler(const string& runname)
     : _runname(runname),
       _initialised(false), _ignoreBeams(false), _skipWeights(false),
       _defaultWeightIdx(0), _dumpPeriod(0), _dumping(false)
   {  }
 
 
-  AnalysisHandler::~AnalysisHandler()
-  {  }
+  AnalysisHandler::~AnalysisHandler() {
+      static bool printed = false;
+    // Print out MCnet boilerplate
+    if (!printed && getLog().getLevel() <= 20) {
+      cout << endl;
+      cout << "The MCnet usage guidelines apply to Rivet: see http://www.montecarlonet.org/GUIDELINES" << endl;
+      cout << "Please acknowledge plots made with Rivet analyses, and cite arXiv:1003.0694 (http://arxiv.org/abs/1003.0694)" << endl;
+      printed = true;
+    }
+  }
 
 
   Log& AnalysisHandler::getLog() const {
     return Log::getLog("Rivet.Analysis.Handler");
   }
 
 
   /// http://stackoverflow.com/questions/4654636/how-to-determine-if-a-string-is-a-number-with-c
   namespace {
     bool is_number(const std::string& s) {
       std::string::const_iterator it = s.begin();
       while (it != s.end() && std::isdigit(*it)) ++it;
       return !s.empty() && it == s.end();
     }
   }
 
   /// Check if any of the weightnames is not a number
   bool AnalysisHandler::haveNamedWeights() const {
     bool dec=false;
     for (unsigned int i=0;i<_weightNames.size();++i) {
       string s = _weightNames[i];
       if (!is_number(s)) {
         dec=true;
         break;
       }
     }
     return dec;
   }
 
 
   void AnalysisHandler::init(const GenEvent& ge) {
     if (_initialised)
       throw UserError("AnalysisHandler::init has already been called: cannot re-initialize!");
 
     /// @todo Should the Rivet analysis objects know about weight names?
 
     setRunBeams(Rivet::beams(ge));
     MSG_DEBUG("Initialising the analysis handler");
     _eventNumber = ge.event_number();
 
     setWeightNames(ge);
     if (_skipWeights)
         MSG_INFO("Only using nominal weight. Variation weights will be ignored.");
     else if (haveNamedWeights())
         MSG_INFO("Using named weights");
     else
         MSG_INFO("NOT using named weights. Using first weight as nominal weight");
 
     _eventCounter = CounterPtr(weightNames(), Counter("_EVTCOUNT"));
 
     // Set the cross section based on what is reported by this event.
     if ( ge.cross_section() ) setCrossSection(HepMCUtils::crossSection(ge));
 
     // Check that analyses are beam-compatible, and remove those that aren't
     const size_t num_anas_requested = analysisNames().size();
     vector<string> anamestodelete;
     for (const AnaHandle a : analyses()) {
       if (!_ignoreBeams && !a->isCompatible(beams())) {
         //MSG_DEBUG(a->name() << " requires beams " << a->requiredBeams() << " @ " << a->requiredEnergies() << " GeV");
         anamestodelete.push_back(a->name());
       }
     }
     for (const string& aname : anamestodelete) {
       MSG_WARNING("Analysis '" << aname << "' is incompatible with the provided beams: removing");
       removeAnalysis(aname);
     }
     if (num_anas_requested > 0 && analysisNames().empty()) {
       cerr << "All analyses were incompatible with the first event's beams\n"
            << "Exiting, since this probably wasn't intentional!" << endl;
       exit(1);
     }
 
     // Warn if any analysis' status is not unblemished
     for (const AnaHandle a : analyses()) {
       if ( a->info().preliminary() ) {
         MSG_WARNING("Analysis '" << a->name() << "' is preliminary: be careful, it may change and/or be renamed!");
       } else if ( a->info().obsolete() ) {
         MSG_WARNING("Analysis '" << a->name() << "' is obsolete: please update!");
       } else if (( a->info().unvalidated() ) ) {
         MSG_WARNING("Analysis '" << a->name() << "' is unvalidated: be careful, it may be broken!");
       }
     }
 
     // Initialize the remaining analyses
     _stage = Stage::INIT;
     for (AnaHandle a : analyses()) {
       MSG_DEBUG("Initialising analysis: " << a->name());
       try {
         // Allow projection registration in the init phase onwards
         a->_allowProjReg = true;
         a->init();
         //MSG_DEBUG("Checking consistency of analysis: " << a->name());
         //a->checkConsistency();
       } catch (const Error& err) {
         cerr << "Error in " << a->name() << "::init method: " << err.what() << endl;
         exit(1);
       }
       MSG_DEBUG("Done initialising analysis: " << a->name());
     }
     _stage = Stage::OTHER;
     _initialised = true;
     MSG_DEBUG("Analysis handler initialised");
   }
 
   void AnalysisHandler::setWeightNames(const GenEvent& ge) {
     if (!_skipWeights)  _weightNames = HepMCUtils::weightNames(ge);
     if ( _weightNames.empty() )  _weightNames.push_back("");
     for ( int i = 0, N = _weightNames.size(); i < N; ++i )
       if ( _weightNames[i] == "" ) _defaultWeightIdx = i;
   }
 
   void AnalysisHandler::analyze(const GenEvent& ge) {
     // Call init with event as template if not already initialised
     if (!_initialised) init(ge);
     assert(_initialised);
 
     // Ensure that beam details match those from the first event (if we're checking beams)
     if ( !_ignoreBeams ) {
       const PdgIdPair beams = Rivet::beamIds(ge);
       const double sqrts = Rivet::sqrtS(ge);
       if (!compatible(beams, _beams) || !fuzzyEquals(sqrts, sqrtS())) {
         cerr << "Event beams mismatch: "
              << PID::toBeamsString(beams) << " @ " << sqrts/GeV << " GeV" << " vs. first beams "
              << this->beams() << " @ " << this->sqrtS()/GeV << " GeV" << endl;
         exit(1);
       }
     }
 
     // Create the Rivet event wrapper
     /// @todo Filter/normalize the event here
     bool strip = ( getEnvParam("RIVET_STRIP_HEPMC", string("NOOOO") ) != "NOOOO" );
     Event event(ge, strip);
 
     // set the cross section based on what is reported by this event.
     // if no cross section
     if ( ge.cross_section() ) setCrossSection(HepMCUtils::crossSection(ge));
 
     // Won't happen for first event because _eventNumber is set in init()
     if (_eventNumber != ge.event_number()) {
 
       pushToPersistent();
 
       _eventNumber = ge.event_number();
 
     }
 
 
     MSG_TRACE("starting new sub event");
     _eventCounter.get()->newSubEvent();
 
     for (const AnaHandle& a : analyses()) {
         for (auto ao : a->analysisObjects()) {
             ao.get()->newSubEvent();
         }
     }
 
     _subEventWeights.push_back(event.weights());
     MSG_DEBUG("Analyzing subevent #" << _subEventWeights.size() - 1 << ".");
 
     _eventCounter->fill();
     // Run the analyses
     for (AnaHandle a : analyses()) {
       MSG_TRACE("About to run analysis " << a->name());
       try {
         a->analyze(event);
       } catch (const Error& err) {
         cerr << "Error in " << a->name() << "::analyze method: " << err.what() << endl;
         exit(1);
       }
       MSG_TRACE("Finished running analysis " << a->name());
     }
 
     if ( _dumpPeriod > 0 && numEvents() > 0 && numEvents()%_dumpPeriod == 0 ) {
       MSG_INFO("Dumping intermediate results to " << _dumpFile << ".");
       _dumping = numEvents()/_dumpPeriod;
       finalize();
       writeData(_dumpFile);
       _dumping = 0;
     }
 
   }
 
 
   void AnalysisHandler::analyze(const GenEvent* ge) {
     if (ge == nullptr) {
       MSG_ERROR("AnalysisHandler received null pointer to GenEvent");
       //throw Error("AnalysisHandler received null pointer to GenEvent");
     }
     analyze(*ge);
   }
 
   void AnalysisHandler::pushToPersistent() {
     if ( _subEventWeights.empty() ) return;
     MSG_TRACE("AnalysisHandler::analyze(): Pushing _eventCounter to persistent.");
     _eventCounter.get()->pushToPersistent(_subEventWeights);
     for (const AnaHandle& a : analyses()) {
       for (auto ao : a->analysisObjects()) {
         MSG_TRACE("AnalysisHandler::analyze(): Pushing " << a->name()
                   << "'s " << ao->name() << " to persistent.");
         ao.get()->pushToPersistent(_subEventWeights);
       }
       MSG_TRACE("AnalysisHandler::analyze(): finished pushing "
                 << a->name() << "'s objects to persistent.");
     }
     _subEventWeights.clear();
   }
 
   void AnalysisHandler::finalize() {
     if (!_initialised) return;
     MSG_INFO("Finalising analyses");
 
     _stage = Stage::FINALIZE;
     
     // First push all analyses' objects to persistent and final
     MSG_TRACE("AnalysisHandler::finalize(): Pushing analysis objects to persistent.");
     pushToPersistent();
 
     // Copy all histos to finalize versions.
     _eventCounter.get()->pushToFinal();
     _xs.get()->pushToFinal();
     for (const AnaHandle& a : analyses())
       for (auto ao : a->analysisObjects())
         ao.get()->pushToFinal();
 
     for (AnaHandle a : analyses()) {
       if ( _dumping && !a->info().reentrant() )  {
         if ( _dumping == 1 )
           MSG_INFO("Skipping finalize in periodic dump of " << a->name()
                    << " as it is not declared reentrant.");
         continue;
       }
       for (size_t iW = 0; iW < numWeights(); iW++) {
         _eventCounter.get()->setActiveFinalWeightIdx(iW);
         _xs.get()->setActiveFinalWeightIdx(iW);
         for (auto ao : a->analysisObjects())
           ao.get()->setActiveFinalWeightIdx(iW);
         try {
           MSG_TRACE("running " << a->name() << "::finalize() for weight " << iW << ".");
           a->finalize();
         } catch (const Error& err) {
           cerr << "Error in " << a->name() << "::finalize method: " << err.what() << '\n';
           exit(1);
         }
       }
     }
 
     // Print out number of events processed
     if (!_dumping) {
       const int nevts = numEvents();
       MSG_INFO("Processed " << nevts << " event" << (nevts != 1 ? "s" : ""));
     }
 
     _stage = Stage::OTHER;
 
-    if ( _dumping ) return;
- 
-    // Print out MCnet boilerplate
-    if (getLog().getLevel()<=20){
-      cout << endl;
-      cout << "The MCnet usage guidelines apply to Rivet: see http://www.montecarlonet.org/GUIDELINES" << endl;
-      cout << "Please acknowledge plots made with Rivet analyses, and cite arXiv:1003.0694 (http://arxiv.org/abs/1003.0694)" << endl;
-    }
   }
 
 
   AnalysisHandler& AnalysisHandler::addAnalysis(const string& analysisname, std::map<string, string> pars) {
      // Make an option handle.
     std::string parHandle = "";
     for (map<string, string>::iterator par = pars.begin(); par != pars.end(); ++par) {
       parHandle +=":";
       parHandle += par->first + "=" + par->second;
     }
     return addAnalysis(analysisname + parHandle);
   }
 
 
   AnalysisHandler& AnalysisHandler::addAnalysis(const string& analysisname) {
     // Check for a duplicate analysis
     /// @todo Might we want to be able to run an analysis twice, with different params?
     ///       Requires avoiding histo tree clashes, i.e. storing the histos on the analysis objects.
     string ananame = analysisname;
     vector<string> anaopt = split(analysisname, ":");
     if ( anaopt.size() > 1 ) ananame = anaopt[0];
     AnaHandle analysis( AnalysisLoader::getAnalysis(ananame) );
     if (analysis.get() != 0) { // < Check for null analysis.
       MSG_DEBUG("Adding analysis '" << analysisname << "'");
       map<string,string> opts;
       for ( int i = 1, N = anaopt.size(); i < N; ++i ) {
         vector<string> opt = split(anaopt[i], "=");
         if ( opt.size() != 2 ) {
           MSG_WARNING("Error in option specification. Skipping analysis " << analysisname);
           return *this;
         }
         if ( !analysis->info().validOption(opt[0], opt[1]) ) {
           MSG_WARNING("Cannot set option '" << opt[0] << "' to '" << opt[1]
                       << "'. Skipping analysis " << analysisname);
           return *this;
         }
         opts[opt[0]] = opt[1];
       }
       for ( auto opt: opts) {
         analysis->_options[opt.first] = opt.second;
         analysis->_optstring += ":" + opt.first + "=" + opt.second;
       }
       for (const AnaHandle& a : analyses()) {
         if (a->name() == analysis->name() ) {
           MSG_WARNING("Analysis '" << analysisname << "' already registered: skipping duplicate");
           return *this;
         }
       }
       analysis->_analysishandler = this;
       _analyses[analysisname] = analysis;
     } else {
       MSG_WARNING("Analysis '" << analysisname << "' not found.");
     }
     // MSG_WARNING(_analyses.size());
     // for (const AnaHandle& a : _analyses) MSG_WARNING(a->name());
     return *this;
   }
 
 
   AnalysisHandler& AnalysisHandler::removeAnalysis(const string& analysisname) {
     MSG_DEBUG("Removing analysis '" << analysisname << "'");
     if (_analyses.find(analysisname) != _analyses.end()) _analyses.erase(analysisname);
     // }
     return *this;
   }
 
 
   // void AnalysisHandler::addData(const std::vector<YODA::AnalysisObjectPtr>& aos) {
   //   for (const YODA::AnalysisObjectPtr ao : aos) {
   //     string path = ao->path();
   //     if ( path.substr(0, 5) != "/RAW/" ) {
   //       _orphanedPreloads.push_back(ao);
   //       continue;
   //     }
 
   //     path = path.substr(4);
   //     ao->setPath(path);
   //     if (path.size() > 1) { // path > "/"
   //       try {
   //         const string ananame =  ::split(path, "/")[0];
   //         AnaHandle a = analysis(ananame);
   //         /// @todo FIXXXXX
   //         //MultiweightAOPtr mao = ????; /// @todo generate right Multiweight object from ao
   //         //a->addAnalysisObject(mao); /// @todo Need to statistically merge...
   //       } catch (const Error& e) {
   //         MSG_TRACE("Adding analysis object " << path <<
   //                   " to the list of orphans.");
   //         _orphanedPreloads.push_back(ao);
   //       }
   //     }
   //   }
   // }
 
 
   void AnalysisHandler::stripOptions(YODA::AnalysisObjectPtr ao,
                                      const vector<string> & delopts) const {
     string path = ao->path();
     string ananame = split(path, "/")[0];
     vector<string> anaopts = split(ananame, ":");
     for ( int i = 1, N = anaopts.size(); i < N; ++i )
       for ( auto opt : delopts )
         if ( opt == "*" || anaopts[i].find(opt + "=") == 0 )
           path.replace(path.find(":" + anaopts[i]), (":" + anaopts[i]).length(), "");
     ao->setPath(path);
   }
 
 
   void AnalysisHandler::mergeYodas(const vector<string> & aofiles,
                                    const vector<string> & delopts, bool equiv) {
 
     // Convenient typedef;
     typedef multimap<string, YODA::AnalysisObjectPtr> AOMap;
 
     // Store all found weights here.
     set<string> foundWeightNames;
 
     // Stor all found analyses.
     set<string> foundAnalyses;
 
     // Store all analysis objects here.
     vector<AOMap> allaos;
 
     // Go through all files and collect information.
     for ( auto file : aofiles ) {
       allaos.push_back(AOMap());
       AOMap & aomap = allaos.back();
       vector<YODA::AnalysisObject*> aos_raw;
       try {
         YODA::read(file, aos_raw);
       }
       catch (...) { //< YODA::ReadError&
         throw UserError("Unexpected error in reading file: " + file);
       }
       for (YODA::AnalysisObject* aor : aos_raw) {
         YODA::AnalysisObjectPtr ao(aor);
         AOPath path(ao->path());
         if ( !path ) 
           throw UserError("Invalid path name in file: " + file);
         if ( !path.isRaw() ) continue;
 
         foundWeightNames.insert(path.weight());
         // Now check if any options should be removed.
         for ( string delopt : delopts )
           if ( path.hasOption(delopt) ) path.removeOption(delopt);
         path.setPath();
         if ( path.analysisWithOptions() != "" )
           foundAnalyses.insert(path.analysisWithOptions());
         aomap.insert(make_pair(path.path(), ao));
       }
     }
 
     // Now make analysis handler aware of the weight names present.
     _weightNames.clear();
     _defaultWeightIdx = 0;
     for ( string name : foundWeightNames ) _weightNames.push_back(name);
 
     // Then we create and initialize all analyses
     for ( string ananame : foundAnalyses ) addAnalysis(ananame);
     _stage = Stage::INIT;
     for (AnaHandle a : analyses() ) {
       MSG_TRACE("Initialising analysis: " << a->name());
       if ( !a->info().reentrant() )
         MSG_WARNING("Analysis " << a->name() << " has not been validated to have "
                     << "a reentrant finalize method. The merged result is unpredictable.");
       try {
         // Allow projection registration in the init phase onwards
         a->_allowProjReg = true;
         a->init();
       } catch (const Error& err) {
         cerr << "Error in " << a->name() << "::init method: " << err.what() << endl;
         exit(1);
       }
       MSG_TRACE("Done initialising analysis: " << a->name());
     }
     _stage = Stage::OTHER;
     _initialised = true;
 
     // Now get all booked analysis objects.
     vector<MultiweightAOPtr> raos;
     for (AnaHandle a : analyses()) {
       for (const auto & ao : a->analysisObjects()) {
         raos.push_back(ao);
       }
     }
 
     // Collect global weights and xcoss sections and fix scaling for
     // all files.
     _eventCounter = CounterPtr(weightNames(), Counter("_EVTCOUNT"));
     _xs = Scatter1DPtr(weightNames(), Scatter1D("_XSEC"));
     for (size_t iW = 0; iW < numWeights(); iW++) {
       _eventCounter.get()->setActiveWeightIdx(iW);
       _xs.get()->setActiveWeightIdx(iW);
       YODA::Counter & sumw = *_eventCounter;
       YODA::Scatter1D & xsec = *_xs;
       vector<YODA::Scatter1DPtr> xsecs;
       vector<YODA::CounterPtr> sows;
       for ( auto & aomap : allaos ) {
         auto xit = aomap.find(xsec.path());
         if ( xit != aomap.end() )
           xsecs.push_back(dynamic_pointer_cast<YODA::Scatter1D>(xit->second));
         else
           xsecs.push_back(YODA::Scatter1DPtr());
         xit = aomap.find(sumw.path());
         if ( xit != aomap.end() )
           sows.push_back(dynamic_pointer_cast<YODA::Counter>(xit->second));
         else
           sows.push_back(YODA::CounterPtr());
       }
       double xs = 0.0, xserr = 0.0;
       for ( int i = 0, N = sows.size(); i < N; ++i ) {
         if ( !sows[i] || !xsecs[i] ) continue;
         double xseci = xsecs[i]->point(0).x();
         double xsecerri = sqr(xsecs[i]->point(0).xErrAvg());
         sumw += *sows[i];
         double effnent = sows[i]->effNumEntries();
         xs += (equiv? effnent: 1.0)*xseci;
         xserr += (equiv? sqr(effnent): 1.0)*xsecerri;
       }
       vector<double> scales(sows.size(), 1.0);
       if ( equiv ) {
         xs /= sumw.effNumEntries();
         xserr = sqrt(xserr)/sumw.effNumEntries();
       } else {
         xserr = sqrt(xserr);
         for ( int i = 0, N = sows.size(); i < N; ++i )
           scales[i] = (sumw.sumW()/sows[i]->sumW())*
            (xsecs[i]->point(0).x()/xs);
       }
       xsec.reset();
       xsec.addPoint(Point1D(xs, xserr));
 
       // Go through alla analyses and add stuff to their analysis objects;
       for (AnaHandle a : analyses()) {
         for (const auto & ao : a->analysisObjects()) {
           ao.get()->setActiveWeightIdx(iW);
           YODA::AnalysisObjectPtr yao = ao.get()->activeYODAPtr();
           for ( int i = 0, N = sows.size(); i < N; ++i ) {
             if ( !sows[i] || !xsecs[i] ) continue;
             auto range = allaos[i].equal_range(yao->path());
             for ( auto aoit = range.first; aoit != range.second; ++aoit )
               if ( !addaos(yao, aoit->second, scales[i]) )
                 MSG_WARNING("Cannot merge objects with path " << yao->path()
                             <<" of type " << yao->annotation("Type") );
           }
           ao.get()->unsetActiveWeight();
         }
       }
       _eventCounter.get()->unsetActiveWeight();
       _xs.get()->unsetActiveWeight();
     }
 
     // Finally we just have to finalize all analyses, leaving to the
     // controlling program to write it out some yoda-file.
     finalize();
 
   }
 
   void AnalysisHandler::readData(const string& filename) {
     try {
       /// @todo Use new YODA SFINAE to fill the smart ptr vector directly
       vector<YODA::AnalysisObject*> aos_raw;
       YODA::read(filename, aos_raw);
       for (YODA::AnalysisObject* aor : aos_raw)
         _preloads[aor->path()] = YODA::AnalysisObjectPtr(aor);
     } catch (...) { //< YODA::ReadError&
       throw UserError("Unexpected error in reading file: " + filename);
     }
   }
 
   vector<MultiweightAOPtr> AnalysisHandler::getRivetAOs() const {
       vector<MultiweightAOPtr> rtn;
 
       for (AnaHandle a : analyses()) {
           for (const auto & ao : a->analysisObjects()) {
               rtn.push_back(ao);
           }
       }
 
       rtn.push_back(_eventCounter);
       rtn.push_back(_xs);
 
       return rtn;
   }
 
   void AnalysisHandler::writeData(const string& filename) const {
 
     // This is where we store the OAs to be written.
     vector<YODA::AnalysisObjectPtr> output;
 
     // First get all multiwight AOs
     vector<MultiweightAOPtr> raos = getRivetAOs();
     output.reserve(raos.size()*2*numWeights());
 
     // Fix the oredering so that default weight is written out first.
     vector<size_t> order;
     if ( _defaultWeightIdx >= 0 && _defaultWeightIdx < numWeights() )
       order.push_back(_defaultWeightIdx);
     for ( size_t  i = 0; i < numWeights(); ++i )
       if ( i != _defaultWeightIdx ) order.push_back(i);
 
     // Then we go through all finalized AOs one weight at a time
     for (size_t iW : order ) {
       for ( auto rao : raos ) {
         rao.get()->setActiveFinalWeightIdx(iW);
         if ( rao->path().find("/TMP/") != string::npos ) continue;
         output.push_back(rao.get()->activeYODAPtr());
       }
     }
 
     // Finally the RAW objects.
     for (size_t iW : order ) {
       for ( auto rao : raos ) {
         rao.get()->setActiveWeightIdx(iW);
         output.push_back(rao.get()->activeYODAPtr());
       }
     }
       
     try {
       YODA::write(filename, output.begin(), output.end());
     } catch (...) { //< YODA::WriteError&
       throw UserError("Unexpected error in writing file: " + filename);
     }
   }
 
 
   string AnalysisHandler::runName() const { return _runname; }
   size_t AnalysisHandler::numEvents() const { return _eventCounter->numEntries(); }
 
 
   std::vector<std::string> AnalysisHandler::analysisNames() const {
     std::vector<std::string> rtn;
     for (AnaHandle a : analyses()) {
       rtn.push_back(a->name());
     }
     return rtn;
   }
 
 
   AnalysisHandler& AnalysisHandler::addAnalyses(const std::vector<std::string>& analysisnames) {
     for (const string& aname : analysisnames) {
       //MSG_DEBUG("Adding analysis '" << aname << "'");
       addAnalysis(aname);
     }
     return *this;
   }
 
 
   AnalysisHandler& AnalysisHandler::removeAnalyses(const std::vector<std::string>& analysisnames) {
     for (const string& aname : analysisnames) {
       removeAnalysis(aname);
     }
     return *this;
   }
 
 
   void AnalysisHandler::setCrossSection(pair<double,double> xsec) {
     _xs = Scatter1DPtr(weightNames(), Scatter1D("_XSEC"));
     _eventCounter.get()->setActiveWeightIdx(_defaultWeightIdx);
     double nomwgt = sumW();
 
     // The cross section of each weight variation is the nominal cross section
     // times the sumW(variation) / sumW(nominal).
     // This way the cross section will work correctly
     for (size_t iW = 0; iW < numWeights(); iW++) {
       _eventCounter.get()->setActiveWeightIdx(iW);
       double s = sumW() / nomwgt;
       _xs.get()->setActiveWeightIdx(iW);
       _xs->addPoint(xsec.first*s, xsec.second*s);
     }
 
     _eventCounter.get()->unsetActiveWeight();
     _xs.get()->unsetActiveWeight();
     return;
   }
 
   AnalysisHandler& AnalysisHandler::addAnalysis(Analysis* analysis) {
     analysis->_analysishandler = this;
     // _analyses.insert(AnaHandle(analysis));
     _analyses[analysis->name()] = AnaHandle(analysis);
     return *this;
   }
 
   PdgIdPair AnalysisHandler::beamIds() const {
     return Rivet::beamIds(beams());
   }
 
 
   double AnalysisHandler::sqrtS() const {
     return Rivet::sqrtS(beams());
   }
 
   void AnalysisHandler::setIgnoreBeams(bool ignore) {
     _ignoreBeams=ignore;
   }
 
   void AnalysisHandler::skipMultiWeights(bool ignore) {
     _skipWeights=ignore;
   }
 
 
 }