libMesh
const_function.h
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1 // The libMesh Finite Element Library.
2 // Copyright (C) 2002-2024 Benjamin S. Kirk, John W. Peterson, Roy H. Stogner
3 
4 // This library is free software; you can redistribute it and/or
5 // modify it under the terms of the GNU Lesser General Public
6 // License as published by the Free Software Foundation; either
7 // version 2.1 of the License, or (at your option) any later version.
8 
9 // This library is distributed in the hope that it will be useful,
10 // but WITHOUT ANY WARRANTY; without even the implied warranty of
11 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 // Lesser General Public License for more details.
13 
14 // You should have received a copy of the GNU Lesser General Public
15 // License along with this library; if not, write to the Free Software
16 // Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
17 
18 
19 #ifndef LIBMESH_CONST_FUNCTION_H
20 #define LIBMESH_CONST_FUNCTION_H
21 
22 // Local includes
23 #include "libmesh/dense_vector.h"
24 #include "libmesh/function_base.h"
25 #include "libmesh/point.h"
26 
27 // C++ includes
28 #include <memory>
29 #include <string>
30 
31 namespace libMesh
32 {
33 
42 template <typename Output=Number>
43 class ConstFunction : public FunctionBase<Output>
44 {
45 public:
46  explicit
47  ConstFunction (const Output & c) : _c(c)
48  {
49  this->_initialized = true;
50  this->_is_time_dependent = false;
51  }
52 
56  ConstFunction (ConstFunction &&) = default;
57  ConstFunction (const ConstFunction &) = default;
58  ConstFunction & operator= (const ConstFunction &) = default;
59  ConstFunction & operator= (ConstFunction &&) = default;
60  virtual ~ConstFunction () = default;
61 
62  virtual Output operator() (const Point &,
63  const Real = 0) override
64  { return _c; }
65 
66  virtual void operator() (const Point &,
67  const Real,
68  DenseVector<Output> & output) override
69  {
70  unsigned int size = output.size();
71  for (unsigned int i=0; i != size; ++i)
72  output(i) = _c;
73  }
74 
75  virtual std::unique_ptr<FunctionBase<Output>> clone() const override
76  {
77  return std::make_unique<ConstFunction<Output>>(_c);
78  }
79 
80 private:
81  Output _c;
82 };
83 
84 } // namespace libMesh
85 
86 #endif // LIBMESH_CONST_FUNCTION_H
bool _initialized
When init() was called so that everything is ready for calls to operator() (...), then this bool is t...
virtual Output operator()(const Point &, const Real=0) override
The libMesh namespace provides an interface to certain functionality in the library.
virtual ~ConstFunction()=default
bool _is_time_dependent
Cache whether or not this function is actually time-dependent.
DIE A HORRIBLE DEATH HERE typedef LIBMESH_DEFAULT_SCALAR_TYPE Real
virtual std::unique_ptr< FunctionBase< Output > > clone() const override
ConstFunction(const Output &c)
Function that returns a single value that never changes.
virtual unsigned int size() const override final
Definition: dense_vector.h:104
Base class for functors that can be evaluated at a point and (optionally) time.
A Point defines a location in LIBMESH_DIM dimensional Real space.
Definition: point.h:39
ConstFunction & operator=(const ConstFunction &)=default