src/gromacs/tables/forcetable.h

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  35 #ifndef GMX_TABLES_FORCETABLE_H
  36 #define GMX_TABLES_FORCETABLE_H
  37
  38 /*! \libinternal \file
  39  * \brief
  40  * Old routines for table generation (will eventually be replaced)
  41  *
  42  * \inlibraryapi
  43  * \author Erik Lindahl <erik.lindahl@gmail.com>
  44  * \ingroup module_tables
  45  */
  46
  47 #include <cstdio>
  48
  49 #include <memory>
  50
  51 #include "gromacs/mdtypes/fcdata.h"
  52 #include "gromacs/mdtypes/forcerec.h"
  53 #include "gromacs/mdtypes/interaction_const.h"
  54 #include "gromacs/utility/real.h"
  55
  56 /*! \brief Flag to select user tables for make_tables */
  57 #define GMX_MAKETABLES_FORCEUSER  (1<<0)
  58 /*! \brief Flag to only make 1,4 pair tables for make_tables */
  59 #define GMX_MAKETABLES_14ONLY     (1<<1)
  60
  61 /*! \brief Enumerated type to describe the interaction types in a table */
  62 enum {
  63     etiCOUL,  //!< Coulomb
  64     etiLJ6,   //!< Dispersion
  65     etiLJ12,  //!< Repulsion
  66     etiNR     //!< Total number of interaction types
  67 };
  68
  69 /*! \brief Function pointer to calculate the grid contribution for coulomb/LJ
  70  *
  71  * Used to tell table_spline3_fill_ewald_lr whether it
  72  * should calculate the grid contribution for electrostatics or LJ.
  73  */
  74 typedef double (*real_space_grid_contribution_computer)(double, double);
  75
  76
  77 /*! \brief Construct tables with the Ewald long-range force interaction
  78  *
  79  * Creates and fills tables of numPoints points with the spacing
  80  * set to 1/tableScaling with the Ewald long-range (mesh) force.
  81  * There are three separate tables with format F, V, FDV0.
  82  * This function interpolates the Ewald mesh potential contribution
  83  * with coefficient beta using a quadratic spline.
  84  * The force is then be interpolated linearly.
  85  *
  86  * \param numPoints     Number of points in the tables
  87  * \param tableScaling  1/spacing, units 1/nm
  88  * \param beta          Ewald splitting parameter, units 1/nm
  89  * \param v_lr          Pointer to function calculating real-space grid contribution
  90  * \returns a set of Ewald correction tables
  91  */
  92 EwaldCorrectionTables
  93 generateEwaldCorrectionTables(int                                   numPoints,
  94                               double                                tableScaling,
  95                               real                                  beta,
  96                               real_space_grid_contribution_computer v_lr);
  97
  98 /*! \brief Compute scaling for the Ewald quadratic spline tables.
  99  *
 100  * \param ic                     Pointer to interaction constant structure
 101  * \param generateCoulombTables  Take the spacing for Coulomb Ewald corrections into account
 102  * \param generateVdwTables      Take the spacing for Van der Waals Ewald corrections into account
 103  * \return The scaling factor in units 1/nm
 104  */
 105 real ewald_spline3_table_scale(const interaction_const_t &ic,
 106                                bool                       generateCoulombTables,
 107                                bool                       generateVdwTables);
 108
 109 /*! \brief Return the real space grid contribution for Ewald
 110  *
 111  *  \param beta  Ewald splitting parameter
 112  *  \param r     Distance for which to calculate the real-space contrib
 113  *  \return      Real space grid contribution for Ewald electrostatics
 114  */
 115 double v_q_ewald_lr(double beta, double r);
 116
 117 /*! \brief Return the real space grid contribution for LJ-Ewald
 118  *
 119  *  \param beta  Ewald splitting parameter
 120  *  \param r     Distance for which to calculate the real-space contrib
 121  *  \return      Real space grid contribution for Ewald Lennard-Jones interaction
 122  */
 123 double v_lj_ewald_lr(double beta, double r);
 124
 125 /*! \brief Return tables for inner loops.
 126  *
 127  * \param fp     Log file pointer
 128  * \param ic     Non-bonded interaction constants
 129  * \param fn     File name from which to read user tables
 130  * \param rtab   Largest interaction distance to tabulate
 131  * \param flags  Flags to select table settings
 132  *
 133  * \return Pointer to inner loop table structure
 134  */
 135 t_forcetable *make_tables(FILE *fp,
 136                           const interaction_const_t *ic,
 137                           const char *fn, real rtab, int flags);
 138
 139 /*! \brief Return a table for bonded interactions,
 140  *
 141  * \param  fplog   Pointer to log file
 142  * \param  fn      File name
 143  * \param  angle   Type of angle: bonds 0, angles 1, dihedrals 2
 144  * \return New bonded table datatype
 145  */
 146 bondedtable_t make_bonded_table(FILE *fplog, const char *fn, int angle);
 147
 148 /*! \brief Construct and return tabulated dispersion and repulsion interactions
 149  *
 150  * This table can be used to compute long-range dispersion corrections.
 151  * Returns pointer owning nothing when tabfn=nullptr.
 152  */
 153 std::unique_ptr<t_forcetable>
 154 makeDispersionCorrectionTable(FILE *fp, const interaction_const_t *ic,
 155                               real rtab, const char *tabfn);
 156
 157 #endif  /* GMX_TABLES_FORCETABLE_H */