src/gromacs/mdtypes/multipletimestepping.h

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  35 #ifndef GMX_MULTIPLETIMESTEPPING_H
  36 #define GMX_MULTIPLETIMESTEPPING_H
  37
  38 #include <bitset>
  39
  40 #include "gromacs/utility/enumerationhelpers.h"
  41
  42 struct t_inputrec;
  43
  44 namespace gmx
  45 {
  46
  47 //! Force group available for selection for multiple time step integration
  48 enum class MtsForceGroups : int
  49 {
  50     LongrangeNonbonded, //!< PME-mesh or Ewald for electrostatics and/or LJ
  51     Nonbonded,          //!< Non-bonded pair interactions
  52     Pair,               //!< Bonded pair interactions
  53     Dihedral,           //!< Dihedrals, including cmap (not restraints)
  54     Angle,              //! Bonded angle potentials (not restraints)
  55     Count               //! The number of groups above
  56 };
  57
  58 static const gmx::EnumerationArray<MtsForceGroups, std::string> mtsForceGroupNames = {
  59     "longrange-nonbonded", "nonbonded", "pair", "dihedral", "angle"
  60 };
  61
  62 //! Setting for a single level for multiple time step integration
  63 struct MtsLevel
  64 {
  65     //! The force group selection for this level;
  66     std::bitset<static_cast<int>(MtsForceGroups::Count)> forceGroups;
  67     //! The factor between the base, fastest, time step and the time step for this level
  68     int stepFactor;
  69 };
  70
  71 /*! \brief Returns the interval in steps at which the non-bonded pair forces are calculated
  72  *
  73  * Note: returns 1 when multiple time-stepping is not activated.
  74  */
  75 int nonbondedMtsFactor(const t_inputrec& ir);
  76
  77 //! (Release) Asserts that all multiple time-stepping requirements on \p ir are fulfilled
  78 void assertMtsRequirements(const t_inputrec& ir);
  79
  80 } // namespace gmx
  81
  82 #endif /* GMX_MULTIPLETIMESTEPPING_H */