ThePEG/LesHouches/MadGraphReader.h

0001 // -*- C++ -*-
0002 //
0003 // MadGraphReader.h is a part of ThePEG - Toolkit for HEP Event Generation
0004 // Copyright (C) 1999-2019 Leif Lonnblad
0005 //
0006 // ThePEG is licenced under version 3 of the GPL, see COPYING for details.
0007 // Please respect the MCnet academic guidelines, see GUIDELINES for details.
0008 //
0009 #ifndef THEPEG_MadGraphReader_H
0010 #define THEPEG_MadGraphReader_H
0011 // This is the declaration of the MadGraphReader class.
0012
0013 #include "ThePEG/LesHouches/LesHouchesFileReader.h"
0014
0015 namespace ThePEG {
0016
0017 /**
0018  * MadGraphReader inherits from LesHouchesFileReader and is able to
0019  * read event files produced by the MadGraph/MadEvent program.
0020  *
0021  * @see \ref MadGraphReaderInterfaces "The interfaces"
0022  * defined for MadGraphReader.
0023  */
0024 class MadGraphReader: public LesHouchesFileReader {
0025
0026 public:
0027
0028    /** @name Standard constructors and destructors. */
0029   //@{
0030   /**
0031    * Default constructor.
0032    */
0033   MadGraphReader()
0034     : fixedScale(91.188*GeV), fixedAEM(0.007546772), fixedAS(0.12),
0035       doInitCuts(false) {}
0036   //@}
0037
0038 public:
0039
0040   /** @name Virtual functions specified by the LesHouchesReader base class. */
0041   //@{
0042   /**
0043    * Open a file or stream with events and read in the run information
0044    * into the corresponding protected variables.
0045    */
0046   virtual void open();
0047
0048   /**
0049    * Scan the file or stream to obtain information about cross section
0050    * weights and particles etc. This function should fill the
0051    * variables corresponding to the /HEPRUP/ common block. The
0052    * function returns the number of events scanned. This version calls
0053    * the base class function and the readjusts the values in HEPRUP to
0054    * cure some inconsistencies in the MadGraph files.
0055    */
0056   virtual long scan();
0057
0058   /**
0059    * Read the next event form the file or stream into the
0060    * corresponding protected variables. Return false if there is no
0061    * more events.
0062    */
0063   virtual bool doReadEvent();
0064   //@}
0065
0066 public:
0067
0068   /** @name Functions used by the persistent I/O system. */
0069   //@{
0070   /**
0071    * Function used to write out object persistently.
0072    * @param os the persistent output stream written to.
0073    */
0074   void persistentOutput(PersistentOStream & os) const;
0075
0076   /**
0077    * Function used to read in object persistently.
0078    * @param is the persistent input stream read from.
0079    * @param version the version number of the object when written.
0080    */
0081   void persistentInput(PersistentIStream & is, int version);
0082   //@}
0083
0084   /**
0085    * Standard Init function used to initialize the interfaces.
0086    */
0087   static void Init();
0088
0089 protected:
0090
0091   /** @name Clone Methods. */
0092   //@{
0093   /**
0094    * Make a simple clone of this object.
0095    * @return a pointer to the new object.
0096    */
0097   virtual IBPtr clone() const;
0098
0099   /** Make a clone of this object, possibly modifying the cloned object
0100    * to make it sane.
0101    * @return a pointer to the new object.
0102    */
0103   virtual IBPtr fullclone() const;
0104   //@}
0105
0106 protected:
0107
0108   /** @name Standard Interfaced functions. */
0109   //@{
0110
0111   /**
0112    * Initialize this object after the setup phase before saving an
0113    * EventGenerator to disk.
0114    * @throws InitException if object could not be initialized properly.
0115    */
0116   virtual void doinit();
0117
0118   /**
0119    * Called from doinit() to extract cuts from the event file and add
0120    * the corresponding objects to the current EventGenerator.
0121    */
0122   CutsPtr initCuts();
0123
0124   /**
0125    * Called from LesHouchesReader::doinit() to extract PDFs from the
0126    * event file and add the corresponding objects to the current
0127    * EventGenerator.
0128    */
0129   virtual void initPDFs();
0130
0131   /**
0132    * Return true if this object needs to be initialized before all
0133    * other objects because it needs to extract cuts from the event file.
0134    */
0135   virtual bool preInitialize() const;
0136
0137   /**
0138    * Finalize this object. Called in the run phase just after a
0139    * run has ended. Used eg. to write out statistics.
0140    */
0141   virtual void dofinish() {
0142     LesHouchesFileReader::dofinish();
0143     if ( stats.accepted() > 0 ) useMe();
0144   }
0145   //@}
0146
0147 protected:
0148
0149   /**
0150    * Interface function to scan a madgraph file and extract
0151    * information about used cuts. The corresponding cut objects are
0152    * created in the Repository and assigned to this reader.
0153    */
0154   string scanCuts(string);
0155
0156   /**
0157    *  Function to extract the number of events from a string
0158    */
0159   long numberOfEvents(string);
0160
0161 protected:
0162
0163   /**
0164    * Fixed scale. Old MadGraph files do not necessarily contain
0165    * information about the factorization (or renormalization)
0166    * scale. In this case this is used instead.
0167    */
0168   Energy fixedScale;
0169
0170   /**
0171    * Fixed \f$\alpha_{EM}\f$.  Old MadGraph files do not necessarily
0172    * contain information about the value of \f$\alpha_{EM}\f$. In this
0173    * case this is used instead.
0174    */
0175   double fixedAEM;
0176
0177   /**
0178    * Fixed \f$\alpha_S\f$.  Old MadGraph files do not necessarily
0179    * contain information about the value of \f$\alpha_S\f$. In this
0180    * case this is used instead.
0181    */
0182   double fixedAS;
0183
0184   /**
0185    * New MadGraph files contain suitable information about cuts used
0186    * in the generation. The non-zero ones are stored in this map.
0187    */
0188   map<string,double> cuts;
0189
0190   /**
0191    * If true, cuts may be extracted from the event file during initialization.
0192    */
0193   bool doInitCuts;
0194
0195 public:
0196
0197   /**
0198    * Exception class used to inform about inability to work with some
0199    * weighted event files.
0200    */
0201   struct WeightedException: public Exception {};
0202
0203 private:
0204
0205   /**
0206    * Describe a concrete class with persistent data.
0207    */
0208   static ClassDescription<MadGraphReader> initMadGraphReader;
0209
0210   /**
0211    * Private and non-existent assignment operator.
0212    */
0213   MadGraphReader & operator=(const MadGraphReader &) = delete;
0214
0215 };
0216
0217 }
0218
0219
0220 #include "ThePEG/Utilities/ClassTraits.h"
0221
0222 namespace ThePEG {
0223
0224 /** @cond TRAITSPECIALIZATIONS */
0225
0226 /**
0227  * This template specialization informs ThePEG about the
0228  * base class of MadGraphReader.
0229  */
0230 template <>
0231 struct BaseClassTrait<MadGraphReader,1>: public ClassTraitsType {
0232   /** Typedef of the base class of MadGraphReader. */
0233   typedef LesHouchesFileReader NthBase;
0234 };
0235
0236 /**
0237  * This template specialization informs ThePEG about the name of the
0238  * MadGraphReader class and the shared object where it is
0239  * defined.
0240  */
0241 template <>
0242 struct ClassTraits<MadGraphReader>
0243   : public ClassTraitsBase<MadGraphReader> {
0244   /** Return the class name. */
0245   static string className() { return "ThePEG::MadGraphReader"; }
0246   /** Return the name of the shared library to be loaded to get
0247    * access to the MadGraphReader class and every other class it uses
0248    * (except the base class). */
0249   static string library() { return "MadGraphReader.so"; }
0250
0251 };
0252
0253 /** @endcond */
0254
0255 }
0256
0257 #endif /* THEPEG_MadGraphReader_H */