include/types/ifunc.h

   1 /*
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   9  *                        VERSION 3.2.0
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  35 #ifdef HAVE_CONFIG_H
  36 #include <config.h>
  37 #endif
  38
  39 #ifndef _ifunc_h
  40 #define _ifunc_h
  41
  42
  43 typedef real t_ifunc(int nbonds,const t_iatom iatoms[],
  44                      const t_iparams iparams[],
  45                      const rvec x[],rvec f[],rvec fshift[],
  46                      const t_pbc *pbc,const t_graph *g,
  47                      real lambda,real *dvdlambda,
  48                      const t_mdatoms *md,t_fcdata *fcd,
  49                      int *ddgatindex);
  50
  51 /*
  52  * The function type t_ifunc() calculates one interaction, using iatoms[]
  53  * and iparams. Within the function the number of atoms to be used is
  54  * known. Within the function only the atomid part of the iatoms[] array
  55  * is supplied, not the type field (see also t_ilist). The function
  56  * returns the potential energy. If pbc==NULL the coordinates in x are
  57  * assumed to be such that no calculation of PBC is necessary,
  58  * If pbc!=NULL a full PBC calculation is performed.
  59  * If g!=NULL it is used for determining the shift forces.
  60  * With domain decomposition ddgatindex can be used for getting global
  61  * atom numbers for warnings and error messages.
  62  * ddgatindex is NULL when domain decomposition is not used.
  63  */
  64
  65 #define IF_NULL       0
  66 #define IF_BOND       1
  67 #define IF_VSITE      1<<1
  68 #define IF_CONSTRAINT 1<<2
  69 #define IF_CHEMBOND   1<<3
  70 #define IF_BTYPE      1<<4
  71 #define IF_ATYPE      1<<5
  72 #define IF_TABULATED  1<<6
  73 #define IF_LIMZERO    1<<7
  74 /* These flags tell to some of the routines what can be done with this
  75  * item in the list.
  76  * With IF_BOND a bonded interaction will be calculated.
  77  * With IF_BTYPE grompp can convert the bond to a Morse potential.
  78  * With IF_BTYPE or IF_ATYPE the bond/angle can be converted to
  79  * a constraint or used for vsite parameter determination by grompp.
  80  * IF_LIMZERO indicates that for a bonded interaction the potential
  81  * does goes to zero for large distances, thus if such an interaction
  82  * it not assigned to any node by the domain decompostion, the simulation
  83  * still continue, if mdrun has been told so.
  84  */
  85 typedef struct
  86 {
  87   const char *name;     /* the name of this function                    */
  88   const char *longname; /* The name for printing etc.                   */
  89   int     nratoms;      /* nr of atoms needed for this function         */
  90   int     nrfpA,nrfpB;  /* number of parameters for this function.      */
  91                         /* this corresponds to the number of params in  */
  92                         /* iparams struct! (see idef.h)                 */
  93   /* A and B are for normal and free energy components respectively.    */
  94   unsigned long   flags;        /* Flags (see above)                            */
  95   int     nrnb_ind;     /* index for nrnb (-1 if unknown)               */
  96   t_ifunc *ifunc;       /* the function it self                         */
  97 } t_interaction_function;
  98
  99 #define NRFPA(ftype) (interaction_function[(ftype)].nrfpA)
 100 #define NRFPB(ftype) (interaction_function[(ftype)].nrfpB)
 101 #define NRFP(ftype)  (NRFPA(ftype)+NRFPB(ftype))
 102 #define NRAL(ftype) (interaction_function[(ftype)].nratoms)
 103
 104 #define IS_CHEMBOND(ftype) (interaction_function[(ftype)].nratoms==2 && interaction_function[(ftype)].flags & IF_CHEMBOND)
 105 /* IS_CHEMBOND tells if function type ftype represents a chemical bond */
 106
 107 /* IS_ANGLE tells if a function type ftype represents an angle
 108  * Per Larsson, 2007-11-06
 109  */
 110 #define IS_ANGLE(ftype) (interaction_function[(ftype)].nratoms==3 && interaction_function[(ftype)].flags & IF_ATYPE)
 111 #define IS_VSITE(ftype) (interaction_function[(ftype)].flags & IF_VSITE)
 112
 113 #define IS_TABULATED(ftype) (interaction_function[(ftype)].flags & IF_TABULATED)
 114
 115 extern const t_interaction_function interaction_function[F_NRE];
 116 /* initialised interaction functions descriptor                         */
 117
 118 #endif