src/gromacs/applied_forces/densityfitting/densityfittingamplitudelookup.cpp

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  35 /*! \internal \file
  36  * \brief
  37  * Implements amplitude lookup for density fitting
  38  *
  39  * \author Christian Blau <blau@kth.se>
  40  * \ingroup module_applied_forces
  41  */
  42 #include "gmxpre.h"
  43
  44 #include "densityfittingamplitudelookup.h"
  45
  46 #include <algorithm>
  47 #include <vector>
  48
  49 #include "gromacs/utility/arrayref.h"
  50
  51 namespace gmx
  52 {
  53 /********************************************************************
  54  * DensityFittingAmplitudeLookup::Impl
  55  */
  56
  57 class DensityFittingAmplitudeLookupImpl
  58 {
  59 public:
  60     DensityFittingAmplitudeLookupImpl()                                         = default;
  61     DensityFittingAmplitudeLookupImpl(const DensityFittingAmplitudeLookupImpl&) = default;
  62     virtual ~DensityFittingAmplitudeLookupImpl()                                = default;
  63
  64     virtual const std::vector<real>& operator()(ArrayRef<const real> /*chargeA*/,
  65                                                 ArrayRef<const real> /*massT*/,
  66                                                 ArrayRef<const int> localIndex) = 0;
  67     virtual std::unique_ptr<DensityFittingAmplitudeLookupImpl> clone()          = 0;
  68 };
  69
  70 namespace
  71 {
  72 class UnitAmplitudes final : public DensityFittingAmplitudeLookupImpl
  73 {
  74 public:
  75     UnitAmplitudes()                      = default;
  76     UnitAmplitudes(const UnitAmplitudes&) = default;
  77     ~UnitAmplitudes() override            = default;
  78     std::unique_ptr<DensityFittingAmplitudeLookupImpl> clone() override;
  79     const std::vector<real>&                           operator()(ArrayRef<const real> /*chargeA*/,
  80                                         ArrayRef<const real> /*massT*/,
  81                                         ArrayRef<const int> localIndex) override;
  82
  83 private:
  84     std::vector<real> amplitude_;
  85 };
  86
  87 std::unique_ptr<DensityFittingAmplitudeLookupImpl> UnitAmplitudes::clone()
  88 {
  89     return std::make_unique<UnitAmplitudes>(*this);
  90 };
  91
  92 const std::vector<real>& UnitAmplitudes::operator()(ArrayRef<const real> /*chargeA*/,
  93                                                     ArrayRef<const real> /*massT*/,
  94                                                     ArrayRef<const int> localIndex)
  95 {
  96     if (amplitude_.size() != localIndex.size())
  97     {
  98         amplitude_.resize(localIndex.size(), 1.);
  99     }
 100
 101     return amplitude_;
 102 }
 103
 104 class ChargesAsAmplitudes final : public DensityFittingAmplitudeLookupImpl
 105 {
 106 public:
 107     ChargesAsAmplitudes()                           = default;
 108     ChargesAsAmplitudes(const ChargesAsAmplitudes&) = default;
 109     ~ChargesAsAmplitudes() override                 = default;
 110     std::unique_ptr<DensityFittingAmplitudeLookupImpl> clone() override;
 111     const std::vector<real>&                           operator()(ArrayRef<const real> chargeA,
 112                                         ArrayRef<const real> /*massT*/,
 113                                         ArrayRef<const int> localIndex) override;
 114
 115 private:
 116     std::vector<real> amplitude_;
 117 };
 118
 119 std::unique_ptr<DensityFittingAmplitudeLookupImpl> ChargesAsAmplitudes::clone()
 120 {
 121     return std::make_unique<ChargesAsAmplitudes>(*this);
 122 };
 123
 124 const std::vector<real>& ChargesAsAmplitudes::operator()(ArrayRef<const real> chargeA,
 125                                                          ArrayRef<const real> /*massT*/,
 126                                                          ArrayRef<const int> localIndex)
 127 {
 128     if (amplitude_.size() != localIndex.size())
 129     {
 130         amplitude_.resize(localIndex.size());
 131     }
 132
 133     std::transform(std::begin(localIndex),
 134                    std::end(localIndex),
 135                    std::begin(amplitude_),
 136                    [&chargeA](gmx::index index) { return chargeA[index]; });
 137     return amplitude_;
 138 }
 139
 140 class MassesAsAmplitudes final : public DensityFittingAmplitudeLookupImpl
 141 {
 142 public:
 143     MassesAsAmplitudes()                          = default;
 144     MassesAsAmplitudes(const MassesAsAmplitudes&) = default;
 145     ~MassesAsAmplitudes() override                = default;
 146     std::unique_ptr<DensityFittingAmplitudeLookupImpl> clone() override;
 147     const std::vector<real>&                           operator()(ArrayRef<const real> /*chargeA*/,
 148                                         ArrayRef<const real> massT,
 149                                         ArrayRef<const int>  localIndex) override;
 150
 151 private:
 152     std::vector<real> amplitude_;
 153 };
 154
 155 std::unique_ptr<DensityFittingAmplitudeLookupImpl> MassesAsAmplitudes::clone()
 156 {
 157     return std::make_unique<MassesAsAmplitudes>(*this);
 158 };
 159
 160 const std::vector<real>& MassesAsAmplitudes::operator()(ArrayRef<const real> /*chargeA*/,
 161                                                         ArrayRef<const real> massT,
 162                                                         ArrayRef<const int>  localIndex)
 163 {
 164     if (amplitude_.size() != localIndex.size())
 165     {
 166         amplitude_.resize(localIndex.size());
 167     }
 168
 169     std::transform(std::begin(localIndex),
 170                    std::end(localIndex),
 171                    std::begin(amplitude_),
 172                    [&massT](gmx::index index) { return massT[index]; });
 173     return amplitude_;
 174 }
 175
 176 } // namespace
 177
 178 /********************************************************************
 179  * DensityFittingAmplitudeLookup
 180  */
 181
 182
 183 DensityFittingAmplitudeLookup::DensityFittingAmplitudeLookup(const DensityFittingAmplitudeMethod& method)
 184 {
 185     switch (method)
 186     {
 187         case DensityFittingAmplitudeMethod::Unity:
 188             impl_ = std::make_unique<UnitAmplitudes>();
 189             break;
 190         case DensityFittingAmplitudeMethod::Mass:
 191             impl_ = std::make_unique<MassesAsAmplitudes>();
 192             break;
 193         case DensityFittingAmplitudeMethod::Charge:
 194             impl_ = std::make_unique<ChargesAsAmplitudes>();
 195             break;
 196         default: break;
 197     }
 198 }
 199
 200 const std::vector<real>& DensityFittingAmplitudeLookup::operator()(ArrayRef<const real> chargeA,
 201                                                                    ArrayRef<const real> massT,
 202                                                                    ArrayRef<const int>  localIndex)
 203 {
 204     return (*impl_)(chargeA, massT, localIndex);
 205 }
 206
 207 DensityFittingAmplitudeLookup::~DensityFittingAmplitudeLookup() = default;
 208
 209 DensityFittingAmplitudeLookup::DensityFittingAmplitudeLookup(const DensityFittingAmplitudeLookup& other) :
 210     impl_(other.impl_->clone())
 211 {
 212 }
 213
 214 DensityFittingAmplitudeLookup& DensityFittingAmplitudeLookup::operator=(const DensityFittingAmplitudeLookup& other)
 215 {
 216     impl_ = other.impl_->clone();
 217     return *this;
 218 }
 219
 220 DensityFittingAmplitudeLookup::DensityFittingAmplitudeLookup(DensityFittingAmplitudeLookup&&) noexcept = default;
 221
 222 DensityFittingAmplitudeLookup& DensityFittingAmplitudeLookup::
 223                                operator=(DensityFittingAmplitudeLookup&&) noexcept = default;
 224
 225 } // namespace gmx