modified_helmholtz_3d_hypersingular_integrand_functor_2.hpp

// Copyright (C) 2011-2012 by the BEM++ Authors
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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#ifndef fiber_modified_helmholtz_3d_hypersingular_integrand_functor_2_hpp
#define fiber_modified_helmholtz_3d_hypersingular_integrand_functor_2_hpp

#include "../common/common.hpp"

#include <cassert>
#include "collection_of_3d_arrays.hpp"
#include "geometrical_data.hpp"
#include "conjugate.hpp"

namespace Fiber
{

template <typename BasisFunctionType_, typename KernelType_,
          typename ResultType_>
class ModifiedHelmholtz3dHypersingularIntegrandFunctor2
{
public:
    typedef BasisFunctionType_ BasisFunctionType;
    typedef KernelType_ KernelType;
    typedef ResultType_ ResultType;
    typedef typename ScalarTraits<ResultType>::RealType CoordinateType;

    void addGeometricalDependencies(size_t& testGeomDeps, size_t& trialGeomDeps) const {
        testGeomDeps |= NORMALS;
        trialGeomDeps |= NORMALS;
    }

    template <template <typename T> class CollectionOf2dSlicesOfConstNdArrays>
    ResultType evaluate(
            const ConstGeometricalDataSlice<CoordinateType>& testGeomData,
            const ConstGeometricalDataSlice<CoordinateType>& trialGeomData,
            const CollectionOf1dSlicesOfConst3dArrays<BasisFunctionType>& testTransfValues,
            const CollectionOf1dSlicesOfConst3dArrays<BasisFunctionType>& trialTransfValues,
            const CollectionOf2dSlicesOfConstNdArrays<KernelType>& kernelValues) const {
        const int dimWorld = 3;

        // Assert that there are at least two scalar-valued kernels
        assert(kernelValues.size() >= 2);
        assert(kernelValues[0].extent(0) == 1);
        assert(kernelValues[0].extent(1) == 1);
        assert(kernelValues[1].extent(0) == 1);
        assert(kernelValues[1].extent(1) == 1);

        // Assert that there are at least two test and trial transformations
        // (function value and surface curl) of correct dimensions
        assert(testTransfValues.size() >= 2);
        assert(trialTransfValues.size() >= 2);
        _1dSliceOfConst3dArray<BasisFunctionType> testValues = testTransfValues[0];
        _1dSliceOfConst3dArray<BasisFunctionType> trialValues = trialTransfValues[0];
        _1dSliceOfConst3dArray<BasisFunctionType> testSurfaceCurls = testTransfValues[1];
        _1dSliceOfConst3dArray<BasisFunctionType> trialSurfaceCurls = trialTransfValues[1];
        assert(testValues.extent(0) == 1);
        assert(trialValues.extent(0) == 1);
        assert((int)testSurfaceCurls.extent(0) == dimWorld);
        assert((int)trialSurfaceCurls.extent(0) == dimWorld);

        // Let K_0(x, y) = K(x, y) and K_1(x, y) = kappa^2 K(x, y).
        // Return
        // K_0(x, y) curl u*(x) . curl v(y) + K_1(x, y) u*(x) v(y) n(x) . n(y)

        BasisFunctionType dotProduct0 = 0.;
        for (int dim = 0; dim < dimWorld; ++dim)
            dotProduct0 += conjugate(testSurfaceCurls(dim)) * trialSurfaceCurls(dim);
        ResultType term0 = kernelValues[0](0, 0) * dotProduct0;
        CoordinateType dotProduct1 = 0.;
        for (int dim = 0; dim < dimWorld; ++dim)
            dotProduct1 += testGeomData.normal(dim) * trialGeomData.normal(dim);
        ResultType term1 = kernelValues[1](0, 0) *
                (dotProduct1 * conjugate(testValues(0)) * trialValues(0));
        return term0 + term1;
    }
};

} // namespace Fiber

#endif