src/gromacs/mdlib/settle.h

   1 /*
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   5  * Mark Abraham, David van der Spoel, Berk Hess, and Erik Lindahl,
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  35 /*! \libinternal \file
  36  * \brief Declares interface to SETTLE code.
  37  *
  38  * \author Berk Hess <hess@kth.se>
  39  * \author Mark Abraham <mark.j.abraham@gmail.com>
  40  * \ingroup module_mdlib
  41  * \inlibraryapi
  42  */
  43
  44 #ifndef GMX_MDLIB_SETTLE_H
  45 #define GMX_MDLIB_SETTLE_H
  46
  47 #include "gromacs/topology/idef.h"
  48
  49 struct gmx_mtop_t;
  50 struct InteractionList;
  51 struct t_inputrec;
  52 struct t_pbc;
  53
  54 namespace gmx
  55 {
  56
  57 template<typename>
  58 class ArrayRef;
  59 template<typename>
  60 class ArrayRefWithPadding;
  61 enum class ConstraintVariable : int;
  62
  63 /* Abstract type for SETTLE that is defined only in the file that uses it */
  64 struct settledata;
  65
  66 /*! \brief Initializes and returns a structure with SETTLE parameters */
  67 settledata* settle_init(const gmx_mtop_t& mtop);
  68
  69 //! Cleans up.
  70 void settle_free(settledata* settled);
  71
  72 /*! \brief Set up the indices for the settle constraints */
  73 void settle_set_constraints(settledata*            settled,
  74                             const InteractionList& il_settle,
  75                             int                    numHomeAtoms,
  76                             const real*            masses,
  77                             const real*            inverseMasses);
  78
  79 /*! \brief Constrain coordinates using SETTLE.
  80  * Can be called on any number of threads.
  81  */
  82 void csettle(settledata*                     settled,     /* The SETTLE structure */
  83              int                             nthread,     /* The number of threads used */
  84              int                             thread,      /* Our thread index */
  85              const t_pbc*                    pbc,         /* PBC data pointer, can be NULL */
  86              ArrayRefWithPadding<const RVec> x,           /* Reference coordinates */
  87              ArrayRefWithPadding<RVec>       xprime,      /* New coords, to be settled */
  88              real                            invdt,       /* 1/delta_t */
  89              ArrayRefWithPadding<RVec>       v,           /* Also constrain v if v!=NULL */
  90              bool                            bCalcVirial, /* Calculate the virial contribution */
  91              tensor                          vir_r_m_dr,  /* sum r x m delta_r */
  92              bool*                           bErrorHasOccurred /* True if a settle error occurred */
  93 );
  94
  95 /*! \brief Analytical algorithm to subtract the components of derivatives
  96  * of coordinates working on settle type constraint.
  97  */
  98 void settle_proj(settledata*          settled,
  99                  ConstraintVariable   econq,
 100                  int                  nsettle,
 101                  const int            iatoms[],
 102                  const t_pbc*         pbc, /* PBC data pointer, can be NULL  */
 103                  ArrayRef<const RVec> x,
 104                  ArrayRef<RVec>       der,
 105                  ArrayRef<RVec>       derp,
 106                  int                  CalcVirAtomEnd,
 107                  tensor               vir_r_m_dder);
 108
 109 } // namespace gmx
 110
 111 #endif