src/gromacs/mdtypes/multipletimestepping.cpp

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  35 #include "gmxpre.h"
  36
  37 #include "multipletimestepping.h"
  38
  39 #include <optional>
  40
  41 #include "gromacs/mdtypes/inputrec.h"
  42 #include "gromacs/mdtypes/pull_params.h"
  43 #include "gromacs/utility/arrayref.h"
  44 #include "gromacs/utility/gmxassert.h"
  45 #include "gromacs/utility/stringutil.h"
  46
  47 namespace gmx
  48 {
  49
  50 int nonbondedMtsFactor(const t_inputrec& ir)
  51 {
  52     GMX_RELEASE_ASSERT(!ir.useMts || ir.mtsLevels.size() == 2, "Only 2 MTS levels supported here");
  53
  54     if (ir.useMts && ir.mtsLevels[1].forceGroups[static_cast<int>(MtsForceGroups::Nonbonded)])
  55     {
  56         return ir.mtsLevels[1].stepFactor;
  57     }
  58     else
  59     {
  60         return 1;
  61     }
  62 }
  63
  64 std::vector<MtsLevel> setupMtsLevels(const GromppMtsOpts& mtsOpts, std::vector<std::string>* errorMessages)
  65 {
  66     std::vector<MtsLevel> mtsLevels;
  67
  68     if (mtsOpts.numLevels != 2)
  69     {
  70         if (errorMessages)
  71         {
  72             errorMessages->push_back("Only mts-levels = 2 is supported");
  73         }
  74     }
  75     else
  76     {
  77         mtsLevels.resize(2);
  78
  79         const std::vector<std::string> inputForceGroups = gmx::splitString(mtsOpts.level2Forces);
  80         auto&                          forceGroups      = mtsLevels[1].forceGroups;
  81         for (const auto& inputForceGroup : inputForceGroups)
  82         {
  83             bool found     = false;
  84             int  nameIndex = 0;
  85             for (const auto& forceGroupName : gmx::mtsForceGroupNames)
  86             {
  87                 if (gmx::equalCaseInsensitive(inputForceGroup, forceGroupName))
  88                 {
  89                     forceGroups.set(nameIndex);
  90                     found = true;
  91                 }
  92                 nameIndex++;
  93             }
  94             if (!found && errorMessages)
  95             {
  96                 errorMessages->push_back(
  97                         gmx::formatString("Unknown MTS force group '%s'", inputForceGroup.c_str()));
  98             }
  99         }
 100
 101         // Make the level 0 use the complement of the force groups of group 1
 102         mtsLevels[0].forceGroups = ~mtsLevels[1].forceGroups;
 103         mtsLevels[0].stepFactor  = 1;
 104
 105         mtsLevels[1].stepFactor = mtsOpts.level2Factor;
 106
 107         if (errorMessages && mtsLevels[1].stepFactor <= 1)
 108         {
 109             errorMessages->push_back("mts-factor should be larger than 1");
 110         }
 111     }
 112
 113     return mtsLevels;
 114 }
 115
 116 bool haveValidMtsSetup(const t_inputrec& ir)
 117 {
 118     return (ir.useMts && ir.mtsLevels.size() == 2 && ir.mtsLevels[1].stepFactor > 1);
 119 }
 120
 121 namespace
 122 {
 123
 124 //! Checks whether \p nstValue is a multiple of the largest MTS step, returns an error string for parameter \p param when this is not the case
 125 std::optional<std::string> checkMtsInterval(ArrayRef<const MtsLevel> mtsLevels, const char* param, const int nstValue)
 126 {
 127     GMX_RELEASE_ASSERT(mtsLevels.size() >= 2, "Need at least two levels for MTS");
 128
 129     const int mtsFactor = mtsLevels.back().stepFactor;
 130     if (nstValue % mtsFactor == 0)
 131     {
 132         return {};
 133     }
 134     else
 135     {
 136         return gmx::formatString("With MTS, %s = %d should be a multiple of mts-factor = %d", param,
 137                                  nstValue, mtsFactor);
 138     }
 139 }
 140
 141 } // namespace
 142
 143 std::vector<std::string> checkMtsRequirements(const t_inputrec& ir)
 144 {
 145     std::vector<std::string> errorMessages;
 146
 147     if (!ir.useMts)
 148     {
 149         return errorMessages;
 150     }
 151
 152     GMX_RELEASE_ASSERT(haveValidMtsSetup(ir), "MTS setup should be valid here");
 153
 154     ArrayRef<const MtsLevel> mtsLevels = ir.mtsLevels;
 155
 156     if (!(ir.eI == eiMD || ir.eI == eiSD1))
 157     {
 158         errorMessages.push_back(gmx::formatString(
 159                 "Multiple time stepping is only supported with integrators %s and %s",
 160                 ei_names[eiMD], ei_names[eiSD1]));
 161     }
 162
 163     if ((EEL_FULL(ir.coulombtype) || EVDW_PME(ir.vdwtype))
 164         && forceGroupMtsLevel(ir.mtsLevels, MtsForceGroups::LongrangeNonbonded) == 0)
 165     {
 166         errorMessages.emplace_back(
 167                 "With long-range electrostatics and/or LJ treatment, the long-range part "
 168                 "has to be part of the mts-level2-forces");
 169     }
 170
 171     std::optional<std::string> mesg;
 172     if (ir.nstcalcenergy > 0)
 173     {
 174         if ((mesg = checkMtsInterval(mtsLevels, "nstcalcenergy", ir.nstcalcenergy)))
 175         {
 176             errorMessages.push_back(mesg.value());
 177         }
 178     }
 179     if ((mesg = checkMtsInterval(mtsLevels, "nstenergy", ir.nstenergy)))
 180     {
 181         errorMessages.push_back(mesg.value());
 182     }
 183     if ((mesg = checkMtsInterval(mtsLevels, "nstlog", ir.nstlog)))
 184     {
 185         errorMessages.push_back(mesg.value());
 186     }
 187     if ((mesg = checkMtsInterval(mtsLevels, "nstfout", ir.nstfout)))
 188     {
 189         errorMessages.push_back(mesg.value());
 190     }
 191     if (ir.efep != efepNO)
 192     {
 193         if ((mesg = checkMtsInterval(mtsLevels, "nstdhdl", ir.fepvals->nstdhdl)))
 194         {
 195             errorMessages.push_back(mesg.value());
 196         }
 197     }
 198     if (mtsLevels.back().forceGroups[static_cast<int>(gmx::MtsForceGroups::Nonbonded)])
 199     {
 200         if ((mesg = checkMtsInterval(mtsLevels, "nstlist", ir.nstlist)))
 201         {
 202             errorMessages.push_back(mesg.value());
 203         }
 204     }
 205
 206     if (ir.bPull)
 207     {
 208         const int pullMtsLevel  = gmx::forceGroupMtsLevel(ir.mtsLevels, gmx::MtsForceGroups::Pull);
 209         const int mtsStepFactor = ir.mtsLevels[pullMtsLevel].stepFactor;
 210         if (ir.pull->nstxout % mtsStepFactor != 0)
 211         {
 212             errorMessages.emplace_back("pull-nstxout should be a multiple of mts-factor");
 213         }
 214         if (ir.pull->nstfout % mtsStepFactor != 0)
 215         {
 216             errorMessages.emplace_back("pull-nstfout should be a multiple of mts-factor");
 217         }
 218     }
 219
 220     return errorMessages;
 221 }
 222
 223 } // namespace gmx