cubicEqn.H
Go to the documentation of this file.
1 /*---------------------------------------------------------------------------*\
2  ========= |
3  \\ / F ield | OpenFOAM: The Open Source CFD Toolbox
4  \\ / O peration | Website: https://openfoam.org
5  \\ / A nd | Copyright (C) 2017-2021 OpenFOAM Foundation
6  \\/ M anipulation |
7 -------------------------------------------------------------------------------
8 License
9  This file is part of OpenFOAM.
10 
11  OpenFOAM is free software: you can redistribute it and/or modify it
12  under the terms of the GNU General Public License as published by
13  the Free Software Foundation, either version 3 of the License, or
14  (at your option) any later version.
15 
16  OpenFOAM is distributed in the hope that it will be useful, but WITHOUT
17  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
18  FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
19  for more details.
20 
21  You should have received a copy of the GNU General Public License
22  along with OpenFOAM. If not, see <http://www.gnu.org/licenses/>.
23 
24 Class
25  Foam::cubicEqn
26 
27 Description
28  Cubic equation of the form a*x^3 + b*x^2 + c*x + d = 0
29 
30 SourceFiles
31  cubicEqnI.H
32  cubicEqn.C
33 
34 \*---------------------------------------------------------------------------*/
35 
36 #ifndef cubicEqn_H
37 #define cubicEqn_H
38 
39 #include "Roots.H"
40 
41 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
42 
43 namespace Foam
44 {
45 
46 /*---------------------------------------------------------------------------*\
47  Class cubicEqn Declaration
48 \*---------------------------------------------------------------------------*/
49 
50 class cubicEqn
51 :
52  public VectorSpace<cubicEqn, scalar, 4>
53 {
54 public:
55 
56  //- Coefficient indexing enumeration
57  struct coefficient
58  {
59  enum {a, b, c, d};
60  };
61 
62 
63  // Constructors
64 
65  //- Construct null
66  inline cubicEqn();
67 
68  //- Construct initialised to zero
69  inline cubicEqn(const Foam::zero);
70 
71  //- Construct from components
72  inline cubicEqn
73  (
74  const scalar a,
75  const scalar b,
76  const scalar c,
77  const scalar d
78  );
79 
80 
81  // Member Functions
82 
83  // Access
84 
85  inline scalar a() const;
86  inline scalar b() const;
87  inline scalar c() const;
88  inline scalar d() const;
89 
90  inline scalar& a();
91  inline scalar& b();
92  inline scalar& c();
93  inline scalar& d();
94 
95  //- Evaluate at x
96  inline scalar value(const scalar x) const;
97 
98  //- Evaluate the derivative at x
99  inline scalar derivative(const scalar x) const;
100 
101  //- Estimate the error of evaluation at x
102  inline scalar error(const scalar x) const;
103 
104  //- Get the roots
105  Roots<3> roots() const;
106 };
107 
108 
109 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
110 
111 } // End namespace Foam
112 
113 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
114 
115 #include "cubicEqnI.H"
116 
117 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
118 
119 #endif
120 
121 // ************************************************************************* //
Templated vector space.
Definition: VectorSpace.H:53
Templated storage for the roots of polynomial equations, plus flags to indicate the nature of the roo...
Definition: Roots.H:64
scalar error(const scalar x) const
Estimate the error of evaluation at x.
Definition: cubicEqnI.H:115
Cubic equation of the form a*x^3 + b*x^2 + c*x + d = 0.
Definition: cubicEqn.H:49
scalar derivative(const scalar x) const
Evaluate the derivative at x.
Definition: cubicEqnI.H:109
Coefficient indexing enumeration.
Definition: cubicEqn.H:56
Roots< 3 > roots() const
Get the roots.
Definition: cubicEqn.C:32
A class representing the concept of 0 used to avoid unnecessary manipulations for objects that are kn...
Definition: zero.H:49
cubicEqn()
Construct null.
Definition: cubicEqnI.H:28
scalar value(const scalar x) const
Evaluate at x.
Definition: cubicEqnI.H:103
Namespace for OpenFOAM.