include/types/ifunc.h

   1 /*
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  35
  36
  37 #ifndef _ifunc_h
  38 #define _ifunc_h
  39
  40 #include "types/idef.h"
  41 #include "types/mdatom.h"
  42 #include "types/fcdata.h"
  43 #include "types/graph.h"
  44 #include "types/pbc.h"
  45
  46 #ifdef __cplusplus
  47 extern "C" {
  48 #endif
  49
  50
  51 typedef real t_ifunc(int nbonds,const t_iatom iatoms[],
  52                      const t_iparams iparams[],
  53                      const rvec x[],rvec f[],rvec fshift[],
  54                      const t_pbc *pbc,const t_graph *g,
  55                      real lambda,real *dvdlambda,
  56                      const t_mdatoms *md,t_fcdata *fcd,
  57                      int *ddgatindex);
  58
  59 /*
  60  * The function type t_ifunc() calculates one interaction, using iatoms[]
  61  * and iparams. Within the function the number of atoms to be used is
  62  * known. Within the function only the atomid part of the iatoms[] array
  63  * is supplied, not the type field (see also t_ilist). The function
  64  * returns the potential energy. If pbc==NULL the coordinates in x are
  65  * assumed to be such that no calculation of PBC is necessary,
  66  * If pbc!=NULL a full PBC calculation is performed.
  67  * If g!=NULL it is used for determining the shift forces.
  68  * With domain decomposition ddgatindex can be used for getting global
  69  * atom numbers for warnings and error messages.
  70  * ddgatindex is NULL when domain decomposition is not used.
  71  */
  72
  73 #define IF_NULL       0
  74 #define IF_BOND       1
  75 #define IF_VSITE      1<<1
  76 #define IF_CONSTRAINT 1<<2
  77 #define IF_CHEMBOND   1<<3
  78 #define IF_BTYPE      1<<4
  79 #define IF_ATYPE      1<<5
  80 #define IF_TABULATED  1<<6
  81 #define IF_LIMZERO    1<<7
  82 /* These flags tell to some of the routines what can be done with this
  83  * item in the list.
  84  * With IF_BOND a bonded interaction will be calculated.
  85  * With IF_BTYPE grompp can convert the bond to a Morse potential.
  86  * With IF_BTYPE or IF_ATYPE the bond/angle can be converted to
  87  * a constraint or used for vsite parameter determination by grompp.
  88  * IF_LIMZERO indicates that for a bonded interaction the potential
  89  * does goes to zero for large distances, thus if such an interaction
  90  * it not assigned to any node by the domain decompostion, the simulation
  91  * still continue, if mdrun has been told so.
  92  */
  93 typedef struct
  94 {
  95   const char *name;     /* the name of this function                    */
  96   const char *longname; /* The name for printing etc.                   */
  97   int     nratoms;      /* nr of atoms needed for this function         */
  98   int     nrfpA,nrfpB;  /* number of parameters for this function.      */
  99                         /* this corresponds to the number of params in  */
 100                         /* iparams struct! (see idef.h)                 */
 101   /* A and B are for normal and free energy components respectively.    */
 102   unsigned long   flags;        /* Flags (see above)                            */
 103   int     nrnb_ind;     /* index for nrnb (-1 if unknown)               */
 104   t_ifunc *ifunc;       /* the function it self                         */
 105 } t_interaction_function;
 106
 107 #define NRFPA(ftype) (interaction_function[(ftype)].nrfpA)
 108 #define NRFPB(ftype) (interaction_function[(ftype)].nrfpB)
 109 #define NRFP(ftype)  (NRFPA(ftype)+NRFPB(ftype))
 110 #define NRAL(ftype) (interaction_function[(ftype)].nratoms)
 111
 112 #define IS_CHEMBOND(ftype) (interaction_function[(ftype)].nratoms==2 && (interaction_function[(ftype)].flags & IF_CHEMBOND))
 113 /* IS_CHEMBOND tells if function type ftype represents a chemical bond */
 114
 115 /* IS_ANGLE tells if a function type ftype represents an angle
 116  * Per Larsson, 2007-11-06
 117  */
 118 #define IS_ANGLE(ftype) (interaction_function[(ftype)].nratoms==3 && (interaction_function[(ftype)].flags & IF_ATYPE))
 119 #define IS_VSITE(ftype) (interaction_function[(ftype)].flags & IF_VSITE)
 120
 121 #define IS_TABULATED(ftype) (interaction_function[(ftype)].flags & IF_TABULATED)
 122
 123 extern const t_interaction_function interaction_function[F_NRE];
 124 /* initialised interaction functions descriptor                         */
 125
 126 #ifdef __cplusplus
 127 }
 128 #endif
 129
 130
 131 #endif