include/Geant4/G4VImportanceAlgorithm.hh

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0025 //
0026 // G4VImportanceAlgorithm
0027 //
0028 // Class description:
0029 //
0030 // This is an interface used by importance sampling to get the
0031 // number of copies and weight a mother particle should be split
0032 // into when crossing a boundary of "importance cells".
0033 // The interface defines the input to be the ratio of the pre over
0034 // the post importance and the weight of the mother track.
0035 // It returns a struct containing the number of copies (including
0036 // the mother track) to be produced and the weight of each track.
0037 // A user defined algorithm deriving from this interface may be used
0038 // by the importance sampling.
0039
0040 // Author: Michael Dressel (CERN), 2002
0041 // ----------------------------------------------------------------------
0042 #ifndef G4VIMPORTANCEALGORITHM_HH
0043 #define G4VIMPORTANCEALGORITHM_HH
0044
0045 #include "G4Nsplit_Weight.hh"
0046
0047 /**
0048  * @brief G4VImportanceAlgorithm is an interface used by importance sampling
0049  * to get the number of copies and weight a mother particle should be split
0050  * into when crossing a boundary of "importance cells".
0051  * The interface defines the input to be the ratio of the pre over the post
0052  * importance and the weight of the mother track.
0053  * It returns a struct containing the number of copies (including the mother
0054  * track) to be produced and the weight of each track.
0055  * A user defined algorithm deriving from this interface may be used by the
0056  * importance sampling.
0057  */
0058
0059 class G4VImportanceAlgorithm
0060 {
0061   public:
0062
0063     /**
0064      * Default Constructor and Destructor.
0065      */
0066     G4VImportanceAlgorithm() = default;
0067     virtual ~G4VImportanceAlgorithm() = default;
0068
0069     /**
0070      * Calculates the number of tracks and their weight according to the
0071      * pre and post importance value and the weight of the mother track.
0072      *  @param[in] ipre "pre" importance value.
0073      *  @param[in] ipost "post" importance value.
0074      *  @param[in] init_w Initial weight value.
0075      *  @returns A struct containing the number of copies (including the
0076      *           mother track) to be produced and the weight of each track.
0077      */
0078     virtual G4Nsplit_Weight Calculate(G4double ipre,
0079                                       G4double ipost,
0080                                       G4double init_w) const = 0;
0081 };
0082
0083 #endif