yieldSurface.hh

/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
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/*   This file is part of the C++-library RFFGen.                              */
/*   Copyright 2015 Lars Lubkoll                                               */
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/*   RFFGen is free software: you can redistribute it and/or modify            */
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#ifndef RFFGEN_EXAMPLES_YIELD_SURFACE_HH
#define RFFGEN_EXAMPLES_YIELD_SURFACE_HH

#include "../linearAlgebra.hh"
#include "../generate.hh"
#include "../finalize.hh"

namespace RFFGen
{
  template <class Matrix>
  auto yieldSurface(double beta, double offset, Matrix sigma = LinearAlgebra::unitMatrix<Matrix>())
  {
    auto i1 = LinearAlgebra::FirstPrincipalInvariant<Matrix>( sigma );
    auto j2 = LinearAlgebra::SecondDeviatoricInvariant<Matrix>( sigma );
    auto f = (beta/LinearAlgebra::dimension<Matrix>())*i1 + j2 - offset;
    return finalize_scalar( f );
  }
}

#endif // RFFGEN_EXAMPLES_YIELD_SURFACE_HH