Evaluator/detail/Evaluator.h

0001 //==========================================================================
0002 //  AIDA Detector description implementation
0003 //--------------------------------------------------------------------------
0004 // Copyright (C) Organisation europeenne pour la Recherche nucleaire (CERN)
0005 // All rights reserved.
0006 //
0007 // For the licensing terms see $DD4hepINSTALL/LICENSE.
0008 // For the list of contributors see $DD4hepINSTALL/doc/CREDITS.
0009 //
0010 //==========================================================================
0011 // -*- C++ -*-
0012 // ---------------------------------------------------------------------------
0013
0014 #ifndef EVALUATOR_DETAIL_EVALUATOR_H
0015 #define EVALUATOR_DETAIL_EVALUATOR_H
0016
0017 #include <ostream>
0018
0019 /// Namespace for the AIDA detector description toolkit
0020 namespace dd4hep  {
0021
0022   /// Namespace containing XML tools.
0023   namespace tools {
0024
0025     /// Evaluator of arithmetic expressions with an extendable dictionary.
0026     /**
0027      * Taken from CLHEP 1.9.2.1
0028      *
0029      * Example:
0030      * @code
0031      *   #include "XmlTools/Evaluator.h"
0032      *   XmlTools::Evaluator eval;
0033      *   eval.setStdMath();
0034      *   double res = eval.evaluate("sin(30*degree)");
0035      *   if (eval.status() != XmlTools::Evaluator::OK) eval.print_error();
0036      * @endcode
0037      *
0038      * @author Evgeni Chernyaev <Evgueni.Tcherniaev@cern.ch>
0039      * @ingroup evaluator
0040      */
0041     class Evaluator::Object {
0042     public:
0043
0044       /**
0045        * List of possible statuses.
0046        * Status of the last operation can be obtained with status().
0047        * In case if status() is an ERROR the corresponding error message
0048        * can be printed with print_error().
0049        *
0050        * @see status
0051        * @see error_position
0052        * @see print_error
0053        */
0054       struct EvalStatus {
0055         /**
0056          * Returns status of the last operation with the evaluator.
0057          */
0058         int status() const;
0059
0060         /**
0061          * Returns result of the last operation with the evaluator.
0062          */
0063         double result() const;
0064
0065         /**
0066          * Returns position in the input string where the problem occured.
0067          */
0068         int error_position(const char* expression) const;
0069
0070         /**
0071          * Prints error message if status() is an ERROR.
0072          */
0073         void print_error(std::ostream& os) const;
0074
0075         /**
0076          * Prints error message if status() is an ERROR using std::cerr.
0077          */
0078         void print_error() const;
0079
0080         char const* thePosition = 0;
0081         int         theStatus = OK;
0082         double      theResult = 0.0;
0083       };
0084
0085       /**
0086        * Constructor.
0087        */
0088
0089       /**
0090        * Sets system of units. Default is the SI system of units.
0091        * To set the CGS (Centimeter-Gram-Second) system of units
0092        * one should call:
0093        *   Object o(100., 1000., 1.0, 1.0, 1.0, 1.0, 1.0);
0094        *
0095        * To set system of units accepted in the GEANT4 simulation toolkit
0096        * one should call:
0097        * @code
0098        *   setSystemOfUnits(1.e+3, 1./1.60217733e-25, 1.e+9, 1./1.60217733e-10,
0099        *                    1.0, 1.0, 1.0);
0100        * @endcode
0101        *
0102        * The basic units in GEANT4 are:
0103        * @code
0104        *   millimeter              (millimeter = 1.)
0105        *   nanosecond              (nanosecond = 1.)
0106        *   Mega electron Volt      (MeV        = 1.)
0107        *   positron charge         (eplus      = 1.)
0108        *   degree Kelvin           (kelvin     = 1.)
0109        *   the amount of substance (mole       = 1.)
0110        *   luminous intensity      (candela    = 1.)
0111        *   radian                  (radian     = 1.)
0112        *   steradian               (steradian  = 1.)
0113        * @endcode
0114        */
0115
0116       Object(double meter = 1.0, double kilogram = 1.0, double second = 1.0, double ampere = 1.0, double kelvin =
0117                             1.0, double mole = 1.0, double candela = 1.0, double radians = 1.0 );
0118
0119       /**
0120        * Destructor.
0121        */
0122       ~Object();
0123
0124       /**
0125        * Evaluates the arithmetic expression given as character string.
0126        * The expression may consist of numbers, variables and functions
0127        * separated by arithmetic (+, - , /, *, ^, **) and logical
0128        * operators (==, !=, >, >=, <, <=, &&, ||).
0129        *
0130        * @param  expression input expression.
0131        * @return result of the evaluation.
0132        * @see status
0133        * @see error_position
0134        * @see print_error
0135        */
0136       EvalStatus evaluate(const char* expression) const;
0137
0138       /**
0139        * Adds to the dictionary a string constant
0140        *
0141        * @param name name of the variable.
0142        * @param value value assigned to the variable.
0143        * @return returns status
0144        */
0145       int setEnviron(const char* name, const char* value);
0146
0147       /**
0148        * Lookup the dictionary for a string constant
0149        *
0150        * @param name name of the variable.
0151        */
0152       std::pair<const char*, int> getEnviron(const char* name) const;
0153
0154       /**
0155        * Adds to the dictionary a variable with given value.
0156        * If a variable with such a name already exist in the dictionary,
0157        * then status will be set to WARNING_EXISTING_VARIABLE.
0158        *
0159        * @param name name of the variable.
0160        * @param value value assigned to the variable.
0161        */
0162       int setVariable(const char* name, double value);
0163
0164       /**
0165        * Adds to the dictionary a variable with an arithmetic expression
0166        * assigned to it.
0167        * If a variable with such a name already exist in the dictionary,
0168        * then status will be set to WARNING_EXISTING_VARIABLE.
0169        *
0170        * @param name name of the variable.
0171        * @param expression arithmetic expression.
0172        */
0173       int setVariable(const char* name, const char* expression);
0174
0175       /**
0176        * Adds to the dictionary a function without parameters.
0177        * If such a function already exist in the dictionary,
0178        * then status will be set to WARNING_EXISTING_FUNCTION.
0179        *
0180        * @param name function name.
0181        * @param fun pointer to the real function in the user code.
0182        */
0183       int setFunction(const char* name, double (*fun)());
0184
0185       /**
0186        * Adds to the dictionary a function with one parameter.
0187        * If such a function already exist in the dictionary,
0188        * then status will be set to WARNING_EXISTING_FUNCTION.
0189        *
0190        * @param name function name.
0191        * @param fun pointer to the real function in the user code.
0192        */
0193       int setFunction(const char* name, double (*fun)(double));
0194
0195       /**
0196        * Adds to the dictionary a function with two parameters.
0197        * If such a function already exist in the dictionary,
0198        * then status will be set to WARNING_EXISTING_FUNCTION.
0199        *
0200        * @param name function name.
0201        * @param fun pointer to the real function in the user code.
0202        */
0203       int setFunction(const char* name, double (*fun)(double, double));
0204
0205       /**
0206        * Adds to the dictionary a function with three parameters.
0207        * If such a function already exist in the dictionary,
0208        * then status will be set to WARNING_EXISTING_FUNCTION.
0209        *
0210        * @param name function name.
0211        * @param fun pointer to the real function in the user code.
0212        */
0213       int setFunction(const char* name, double (*fun)(double, double, double));
0214
0215       /**
0216        * Adds to the dictionary a function with four parameters.
0217        * If such a function already exist in the dictionary,
0218        * then status will be set to WARNING_EXISTING_FUNCTION.
0219        *
0220        * @param name function name.
0221        * @param fun pointer to the real function in the user code.
0222        */
0223       int setFunction(const char* name, double (*fun)(double, double, double, double));
0224
0225       /**
0226        * Adds to the dictionary a function with five parameters.
0227        * If such a function already exist in the dictionary,
0228        * then status will be set to WARNING_EXISTING_FUNCTION.
0229        *
0230        * @param name function name.
0231        * @param fun pointer to the real function in the user code.
0232        */
0233       int setFunction(const char* name, double (*fun)(double, double, double, double, double));
0234
0235       /**
0236        * Finds the variable in the dictionary.
0237        *
0238        * @param  name name of the variable.
0239        * @return true if such a variable exists, false otherwise.
0240        */
0241       bool findVariable(const char* name) const;
0242
0243       /**
0244        * Finds the function in the dictionary.
0245        *
0246        * @param  name name of the function to be unset.
0247        * @param  npar number of parameters of the function.
0248        * @return true if such a function exists, false otherwise.
0249        */
0250       bool findFunction(const char* name, int npar) const;
0251
0252       /**
0253        * Removes the variable from the dictionary.
0254        *
0255        * @param name name of the variable.
0256        */
0257       void removeVariable(const char* name);
0258
0259       /**
0260        * Removes the function from the dictionary.
0261        *
0262        * @param name name of the function to be unset.
0263        * @param npar number of parameters of the function.
0264        */
0265       void removeFunction(const char* name, int npar);
0266
0267       /**
0268        * Clear all settings.
0269        */
0270       void clear();
0271
0272       struct Struct;
0273
0274     private:
0275       /**
0276        * Sets system of units. Default is the SI system of units.
0277        * To set the CGS (Centimeter-Gram-Second) system of units
0278        * one should call:
0279        *   setSystemOfUnits(100., 1000., 1.0, 1.0, 1.0, 1.0, 1.0);
0280        *
0281        * To set system of units accepted in the GEANT4 simulation toolkit
0282        * one should call:
0283        * @code
0284        *   setSystemOfUnits(1.e+3, 1./1.60217733e-25, 1.e+9, 1./1.60217733e-10,
0285        *                    1.0, 1.0, 1.0);
0286        * @endcode
0287        *
0288        * The basic units in GEANT4 are:
0289        * @code
0290        *   millimeter              (millimeter = 1.)
0291        *   nanosecond              (nanosecond = 1.)
0292        *   Mega electron Volt      (MeV        = 1.)
0293        *   positron charge         (eplus      = 1.)
0294        *   degree Kelvin           (kelvin     = 1.)
0295        *   the amount of substance (mole       = 1.)
0296        *   luminous intensity      (candela    = 1.)
0297        *   radian                  (radian     = 1.)
0298        *   steradian               (steradian  = 1.)
0299        * @endcode
0300        */
0301       void setSystemOfUnits(double meter, double kilogram, double second, double ampere, double kelvin
0302                           , double mole, double candela, double radians );
0303
0304       /**
0305        * Sets standard mathematical functions and constants.
0306        */
0307       void setStdMath();
0308
0309       /**
0310        * Used only during construction
0311        */
0312       void setVariableNoLock(const char* name, double value);
0313       void setFunctionNoLock(const char* name, double (*fun)(double));
0314       void setFunctionNoLock(const char* name, double (*fun)(double, double));
0315
0316
0317       Struct* imp {0};                               // private data
0318       Object(const Object &) = delete;               // copy constructor is not allowed
0319       Object & operator=(const Object &) = delete;   // assignment is not allowed
0320     };
0321
0322   }   // namespace tools
0323 }  // namespace dd4hep
0324
0325 #endif // EVALUATOR_DETAIL_EVALUATOR_H