TrustRegionSubProblem.h

// Copyright 2024, UChicago Argonne, LLC
// All Rights Reserved
// Software Name: NEML2 -- the New Engineering material Model Library, version 2
// By: Argonne National Laboratory
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#pragma once
 
#include "neml2/solvers/NonlinearSystem.h"
#include "neml2/tensors/Scalar.h"
 
namespace neml2
{
class TrustRegionSubProblem : public NonlinearSystem
{
public:
  TrustRegionSubProblem(const OptionSet & options);
 
  virtual void reinit(const NonlinearSystem & system, const Scalar & delta);
 
  Tensor preconditioned_direction(const Scalar & s) const;
 
protected:
  virtual void assemble(bool residual, bool Jacobian) override;
 
  Tensor preconditioned_solve(const Scalar & s, const Tensor & v) const;
 
  TensorShape _batch_sizes;
 
  torch::TensorOptions _options;
 
private:
  Tensor _R;
 
  Tensor _J;
 
  Scalar _delta;
 
  Tensor _JJ;
 
  Tensor _JR;
};
} // namespace neml2