parsed_function.h

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// -----------------------------------------------------------------------------
//
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception OR LGPL-2.1-or-later
// Copyright (C) 2007 - 2025 by the deal.II authors
//
// This file is part of the deal.II library.
//
// Detailed license information governing the source code and contributions
// can be found in LICENSE.md and CONTRIBUTING.md at the top level directory.
//
// -----------------------------------------------------------------------------
 
 
#ifndef dealii_parsed_function_h
#define dealii_parsed_function_h
 
#include <deal.II/base/config.h>
 
#include <deal.II/base/auto_derivative_function.h>
#include <deal.II/base/function_parser.h>
 
DEAL_II_NAMESPACE_OPEN
 
#ifndef DOXYGEN
class ParameterHandler;
#endif
 
namespace Functions
{
  template <int dim>
  class ParsedFunction : public AutoDerivativeFunction<dim>
  {
  public:
    ParsedFunction(const unsigned int n_components = 1, const double h = 1e-8);
 
    static void
    declare_parameters(ParameterHandler  &prm,
                       const unsigned int n_components = 1,
                       const std::string &input_expr   = "");
 
    void
    parse_parameters(ParameterHandler &prm);
 
    virtual void
    vector_value(const Point<dim> &p, Vector<double> &values) const override;
 
    virtual double
    value(const Point<dim> &p, const unsigned int component = 0) const override;
 
    virtual void
    set_time(const double newtime) override;
 
  private:
    FunctionParser<dim> function_object;
  };
} // namespace Functions
 
DEAL_II_NAMESPACE_CLOSE
 
#endif