PathmanathanInteractionForce.cpp

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*/
 
#include "PathmanathanInteractionForce.hpp"
 
template <unsigned ELEMENT_DIM, unsigned SPACE_DIM>
PathmanathanInteractionForce<ELEMENT_DIM,SPACE_DIM>::PathmanathanInteractionForce()
   : AbstractVariableSizeTwoBodyInteractionForce<ELEMENT_DIM,SPACE_DIM>(),
     mAlpha(5.0)
{}
 
template<unsigned ELEMENT_DIM, unsigned SPACE_DIM>
PathmanathanInteractionForce<ELEMENT_DIM,SPACE_DIM>::~PathmanathanInteractionForce()
{
}
 
template<unsigned ELEMENT_DIM, unsigned SPACE_DIM>
c_vector<double, SPACE_DIM> PathmanathanInteractionForce<ELEMENT_DIM,SPACE_DIM>::CalculateLinkInteraction(double overlap,
                                                                                                                   double restLength,
                                                                                                                   const c_vector<double, SPACE_DIM>& rUnitDifference,
                                                                                                                   double multiplicationFactor)
{
    // Pathmanathan force: logarithmic repulsion / exponential attraction
    if (overlap <= 0)
    {
        assert(overlap > -restLength);
        return multiplicationFactor * this->mSpringStiffness * rUnitDifference * restLength * log(1.0 + overlap/restLength);
    }
    else
    {
        return multiplicationFactor * this->mSpringStiffness * rUnitDifference * overlap * exp(-mAlpha * overlap/restLength);
    }
}
 
template<unsigned ELEMENT_DIM, unsigned SPACE_DIM>
double PathmanathanInteractionForce<ELEMENT_DIM,SPACE_DIM>::GetAlpha()
{
    return mAlpha;
}
 
template<unsigned ELEMENT_DIM, unsigned SPACE_DIM>
void PathmanathanInteractionForce<ELEMENT_DIM,SPACE_DIM>::SetAlpha(double alpha)
{
    assert(alpha > 0.0);
    mAlpha = alpha;
}
 
template<unsigned ELEMENT_DIM, unsigned SPACE_DIM>
void PathmanathanInteractionForce<ELEMENT_DIM,SPACE_DIM>::OutputForceParameters(out_stream& rParamsFile)
{
    *rParamsFile << "\t\t\t<SpringStiffness>" << this->mSpringStiffness << "</SpringStiffness>\n";
    *rParamsFile << "\t\t\t<DivisionRestingSpringLength>" << this->mDivisionRestingSpringLength << "</DivisionRestingSpringLength>\n";
    *rParamsFile << "\t\t\t<SpringGrowthDuration>" << this->mSpringGrowthDuration << "</SpringGrowthDuration>\n";
    *rParamsFile << "\t\t\t<Alpha>" << mAlpha << "</Alpha>\n";
 
    // Call method on direct parent class
    AbstractVariableSizeTwoBodyInteractionForce<ELEMENT_DIM,SPACE_DIM>::OutputForceParameters(rParamsFile);
}
 
// Explicit instantiation
template class PathmanathanInteractionForce<1,1>;
template class PathmanathanInteractionForce<1,2>;
template class PathmanathanInteractionForce<2,2>;
template class PathmanathanInteractionForce<1,3>;
template class PathmanathanInteractionForce<2,3>;
template class PathmanathanInteractionForce<3,3>;
 
// Serialization for Boost >= 1.36
#include "SerializationExportWrapperForCpp.hpp"
EXPORT_TEMPLATE_CLASS_ALL_DIMS(PathmanathanInteractionForce)