Added AmoebaMultipoleForce::getPMEParametersInContext()

plugins/amoeba/openmmapi/include/openmm/AmoebaMultipoleForce.h

@@ -175,6 +175,20 @@ public:
      */
     void setPmeGridDimensions(const std::vector<int>& gridDimension);
 
+    /**
+     * Get the parameters being used for PME in a particular Context.  Because some platforms have restrictions
+     * on the allowed grid sizes, the values that are actually used may be slightly different from those
+     * specified with setPmeGridDimensions(), or the standard values calculated based on the Ewald error tolerance.
+     * See the manual for details.
+     * 
+     * @param context the Context for which to get the parameters
+     * @param alpha   the separation parameter
+     * @param nx      the number of grid points along the X axis
+     * @param ny      the number of grid points along the Y axis
+     * @param nz      the number of grid points along the Z axis
+     */
+    void getPMEParametersInContext(const Context& context, double& alpha, int& nx, int& ny, int& nz) const;
+
     /**
      * Add multipole-related info for a particle
      *

plugins/amoeba/openmmapi/include/openmm/amoebaKernels.h

@@ -9,7 +9,7 @@
  * Biological Structures at Stanford, funded under the NIH Roadmap for        *
  * Medical Research, grant U54 GM072970. See https://simtk.org.               *
  *                                                                            *
- * Portions copyright (c) 2008-2012 Stanford University and the Authors.      *
+ * Portions copyright (c) 2008-2015 Stanford University and the Authors.      *
  * Authors:                                                                   *
  * Contributors:                                                              *
  *                                                                            *
@@ -361,6 +361,16 @@ public:
      * @param force      the AmoebaMultipoleForce to copy the parameters from
      */
     virtual void copyParametersToContext(ContextImpl& context, const AmoebaMultipoleForce& force) = 0;
+
+    /**
+     * Get the parameters being used for PME.
+     * 
+     * @param alpha   the separation parameter
+     * @param nx      the number of grid points along the X axis
+     * @param ny      the number of grid points along the Y axis
+     * @param nz      the number of grid points along the Z axis
+     */
+    virtual void getPMEParameters(double& alpha, int& nx, int& ny, int& nz) const = 0;
 };
 
 /**

plugins/amoeba/openmmapi/include/openmm/internal/AmoebaMultipoleForceImpl.h

@@ -89,6 +89,7 @@ public:
 
     void getSystemMultipoleMoments(ContextImpl& context, std::vector< double >& outputMultipoleMoments);
     void updateParametersInContext(ContextImpl& context);
+    void getPMEParameters(double& alpha, int& nx, int& ny, int& nz) const;
  
 
 private:

plugins/amoeba/openmmapi/src/AmoebaMultipoleForce.cpp

@@ -103,6 +103,10 @@ void AmoebaMultipoleForce::setPmeGridDimensions(const std::vector<int>& gridDime
     return;
 } 
 
+void AmoebaMultipoleForce::getPMEParametersInContext(const Context& context, double& alpha, int& nx, int& ny, int& nz) const {
+    dynamic_cast<const AmoebaMultipoleForceImpl&>(getImplInContext(context)).getPMEParameters(alpha, nx, ny, nz);
+}
+
 int AmoebaMultipoleForce::getMutualInducedMaxIterations() const {
     return mutualInducedMaxIterations;
 }

plugins/amoeba/openmmapi/src/AmoebaMultipoleForceImpl.cpp

@@ -199,3 +199,7 @@ void AmoebaMultipoleForceImpl::getSystemMultipoleMoments(ContextImpl& context, s
 void AmoebaMultipoleForceImpl::updateParametersInContext(ContextImpl& context) {
     kernel.getAs<CalcAmoebaMultipoleForceKernel>().copyParametersToContext(context, owner);
 }
+
+void AmoebaMultipoleForceImpl::getPMEParameters(double& alpha, int& nx, int& ny, int& nz) const {
+    kernel.getAs<CalcAmoebaMultipoleForceKernel>().getPMEParameters(alpha, nx, ny, nz);
+}

plugins/amoeba/platforms/cuda/src/AmoebaCudaKernels.cpp

@@ -37,6 +37,7 @@
 #include "openmm/internal/AmoebaVdwForceImpl.h"
 #include "openmm/internal/NonbondedForceImpl.h"
 #include "CudaBondedUtilities.h"
+#include "CudaFFT3D.h"
 #include "CudaForceInfo.h"
 #include "CudaKernelSources.h"
 #include "CudaNonbondedUtilities.h"
@@ -902,26 +903,6 @@ CudaCalcAmoebaMultipoleForceKernel::~CudaCalcAmoebaMultipoleForceKernel() {
         cufftDestroy(fft);
 }
 
-/**
- * Select a size for an FFT that is a multiple of 2, 3, 5, and 7.
- */
-static int findFFTDimension(int minimum) {
-    if (minimum < 1)
-        return 1;
-    while (true) {
-        // Attempt to factor the current value.
-
-        int unfactored = minimum;
-        for (int factor = 2; factor < 8; factor++) {
-            while (unfactored > 1 && unfactored%factor == 0)
-                unfactored /= factor;
-        }
-        if (unfactored == 1)
-            return minimum;
-        minimum++;
-    }
-}
-
 void CudaCalcAmoebaMultipoleForceKernel::initialize(const System& system, const AmoebaMultipoleForce& force) {
     cu.setAsCurrent();
 
@@ -1063,7 +1044,7 @@ void CudaCalcAmoebaMultipoleForceKernel::initialize(const System& system, const
     }
     else
         maxInducedIterations = 0;
-    bool usePME = (force.getNonbondedMethod() == AmoebaMultipoleForce::PME);
+    usePME = (force.getNonbondedMethod() == AmoebaMultipoleForce::PME);
     
     // See whether there's an AmoebaGeneralizedKirkwoodForce in the System.
 
@@ -1099,8 +1080,7 @@ void CudaCalcAmoebaMultipoleForceKernel::initialize(const System& system, const
     int endExclusionIndex = (cu.getContextIndex()+1)*numExclusionTiles/numContexts;
     defines["FIRST_EXCLUSION_TILE"] = cu.intToString(startExclusionIndex);
     defines["LAST_EXCLUSION_TILE"] = cu.intToString(endExclusionIndex);
-    double alpha = force.getAEwald();
-    int gridSizeX, gridSizeY, gridSizeZ;
+    alpha = force.getAEwald();
     if (usePME) {
         vector<int> pmeGridDimension;
         force.getPmeGridDimensions(pmeGridDimension);
@@ -1109,13 +1089,13 @@ void CudaCalcAmoebaMultipoleForceKernel::initialize(const System& system, const
             nb.setEwaldErrorTolerance(force.getEwaldErrorTolerance());
             nb.setCutoffDistance(force.getCutoffDistance());
             NonbondedForceImpl::calcPMEParameters(system, nb, alpha, gridSizeX, gridSizeY, gridSizeZ);
-            gridSizeX = findFFTDimension(gridSizeX);
-            gridSizeY = findFFTDimension(gridSizeY);
-            gridSizeZ = findFFTDimension(gridSizeZ);
+            gridSizeX = CudaFFT3D::findLegalDimension(gridSizeX);
+            gridSizeY = CudaFFT3D::findLegalDimension(gridSizeY);
+            gridSizeZ = CudaFFT3D::findLegalDimension(gridSizeZ);
         } else {
-            gridSizeX = pmeGridDimension[0];
-            gridSizeY = pmeGridDimension[1];
-            gridSizeZ = pmeGridDimension[2];
+            gridSizeX = CudaFFT3D::findLegalDimension(pmeGridDimension[0]);
+            gridSizeY = CudaFFT3D::findLegalDimension(pmeGridDimension[1]);
+            gridSizeZ = CudaFFT3D::findLegalDimension(pmeGridDimension[2]);
         }
         defines["EWALD_ALPHA"] = cu.doubleToString(alpha);
         defines["SQRT_PI"] = cu.doubleToString(sqrt(M_PI));
@@ -2035,6 +2015,15 @@ void CudaCalcAmoebaMultipoleForceKernel::copyParametersToContext(ContextImpl& co
     multipolesAreValid = false;
 }
 
+void CudaCalcAmoebaMultipoleForceKernel::getPMEParameters(double& alpha, int& nx, int& ny, int& nz) const {
+    if (!usePME)
+        throw OpenMMException("getPMEParametersInContext: This Context is not using PME");
+    alpha = this->alpha;
+    nx = gridSizeX;
+    ny = gridSizeY;
+    nz = gridSizeZ;
+}
+
 /* -------------------------------------------------------------------------- *
  *                       AmoebaGeneralizedKirkwood                            *
  * -------------------------------------------------------------------------- */

plugins/amoeba/platforms/cuda/src/AmoebaCudaKernels.h

@@ -363,6 +363,15 @@ public:
      * @param force      the AmoebaMultipoleForce to copy the parameters from
      */
     void copyParametersToContext(ContextImpl& context, const AmoebaMultipoleForce& force);
+    /**
+     * Get the parameters being used for PME.
+     * 
+     * @param alpha   the separation parameter
+     * @param nx      the number of grid points along the X axis
+     * @param ny      the number of grid points along the Y axis
+     * @param nz      the number of grid points along the Z axis
+     */
+    void getPMEParameters(double& alpha, int& nx, int& ny, int& nz) const;
 private:
     class ForceInfo;
     class SortTrait : public CudaSort::SortTrait {
@@ -381,8 +390,9 @@ private:
     template <class T, class T4, class M4> void computeSystemMultipoleMoments(ContextImpl& context, std::vector<double>& outputMultipoleMoments);
     int numMultipoles, maxInducedIterations;
     int fixedFieldThreads, inducedFieldThreads, electrostaticsThreads;
-    double inducedEpsilon;
-    bool hasQuadrupoles, hasInitializedScaleFactors, hasInitializedFFT, multipolesAreValid;
+    int gridSizeX, gridSizeY, gridSizeZ;
+    double alpha, inducedEpsilon;
+    bool usePME, hasQuadrupoles, hasInitializedScaleFactors, hasInitializedFFT, multipolesAreValid;
     CudaContext& cu;
     const System& system;
     std::vector<int3> covalentFlagValues;

plugins/amoeba/platforms/cuda/tests/TestCudaAmoebaMultipoleForce.cpp

@@ -1943,7 +1943,16 @@ static void setupAndGetForcesEnergyMultipoleLargeWater(AmoebaMultipoleForce::Non
         energy                    = state.getPotentialEnergy();
     }
 
-    return;
+    if (nonbondedMethod == AmoebaMultipoleForce::PME) {
+        double actualAlpha;
+        int actualSize[3];
+        amoebaMultipoleForce->getPMEParametersInContext(context, actualAlpha, actualSize[0], actualSize[1], actualSize[2]);
+        ASSERT_EQUAL_TOL(amoebaMultipoleForce->getAEwald(), actualAlpha, 1e-5);
+        for (int i = 0; i < 3; i++) {
+            ASSERT(actualSize[i] >= inputPmeGridDimension);
+            ASSERT(actualSize[i] < inputPmeGridDimension+10);
+        }
+    }
 }
 
 // test multipole mutual polarization using PME for box of water

plugins/amoeba/platforms/reference/src/AmoebaReferenceKernels.cpp

@@ -790,6 +790,15 @@ void ReferenceCalcAmoebaMultipoleForceKernel::copyParametersToContext(ContextImp
     }
 }
 
+void ReferenceCalcAmoebaMultipoleForceKernel::getPMEParameters(double& alpha, int& nx, int& ny, int& nz) const {
+    if (!usePme)
+        throw OpenMMException("getPMEParametersInContext: This Context is not using PME");
+    alpha = alphaEwald;
+    nx = pmeGridDimension[0];
+    ny = pmeGridDimension[1];
+    nz = pmeGridDimension[2];
+}
+
 /* -------------------------------------------------------------------------- *
  *                       AmoebaGeneralizedKirkwood                            *
  * -------------------------------------------------------------------------- */

plugins/amoeba/platforms/reference/src/AmoebaReferenceKernels.h

@@ -9,7 +9,7 @@
  * Biological Structures at Stanford, funded under the NIH Roadmap for        *
  * Medical Research, grant U54 GM072970. See https://simtk.org.               *
  *                                                                            *
- * Portions copyright (c) 2008 Stanford University and the Authors.           *
+ * Portions copyright (c) 2008-2015 Stanford University and the Authors.      *
  * Authors:                                                                   *
  * Contributors:                                                              *
  *                                                                            *
@@ -403,6 +403,15 @@ public:
      * @param force      the AmoebaMultipoleForce to copy the parameters from
      */
     void copyParametersToContext(ContextImpl& context, const AmoebaMultipoleForce& force);
+    /**
+     * Get the parameters being used for PME.
+     * 
+     * @param alpha   the separation parameter
+     * @param nx      the number of grid points along the X axis
+     * @param ny      the number of grid points along the Y axis
+     * @param nz      the number of grid points along the Z axis
+     */
+    void getPMEParameters(double& alpha, int& nx, int& ny, int& nz) const;
 
 private:
 

plugins/amoeba/platforms/reference/tests/TestReferenceAmoebaMultipoleForce.cpp

@@ -1864,7 +1864,16 @@ static void setupAndGetForcesEnergyMultipoleLargeWater(AmoebaMultipoleForce::Non
         energy                    = state.getPotentialEnergy();
     }
 
-    return;
+    if (nonbondedMethod == AmoebaMultipoleForce::PME) {
+        double actualAlpha;
+        int actualSize[3];
+        amoebaMultipoleForce->getPMEParametersInContext(context, actualAlpha, actualSize[0], actualSize[1], actualSize[2]);
+        ASSERT_EQUAL_TOL(amoebaMultipoleForce->getAEwald(), actualAlpha, 1e-5);
+        for (int i = 0; i < 3; i++) {
+            ASSERT(actualSize[i] >= inputPmeGridDimension);
+            ASSERT(actualSize[i] < inputPmeGridDimension+10);
+        }
+    }
 }
 
 // test multipole mutual polarization using PME for box of water