Cosine.H

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License
    This file is part of OpenFOAM.
 
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Class
    Foam::Function1Types::Cosine
 
Description
    A templated cosine function, with support for offset etc.
 
    The wave period can be specified directly
 
        \f[
            a cos(2 \pi (t - t0) / p)) s + l
        \f]
 
    Or it can be specified by the frequency
 
        \f[
            a cos(2 \pi f (t - t0)) s + l
        \f]
 
    where
    \vartable
        Symbol  | Description       | Units
        a       | Amplitude         | -
        f       | Frequency         | [1/s]
        p       | Period            | [s]
        s       | Type scale factor | -
        l       | Type offset level | -
        t       | Time              | [s]
        t0      | Start time offset | [s]
    \endvartable
 
    The dictionary specification would typically resemble this:
    \verbatim
    entry1
    {
        type        cosine;
        frequency   10;
        amplitude   0.1;
 
        // A scalar Function1
        scale       2e-6;
        level       2e-6;
    }
    entry2
    {
        type        cosine;
        frequency   10;
 
        // A vector Function1
        scale       (1 0.1 0);
        level       (10 1 0);
    }
    \endverbatim
 
    where the entries mean:
    \table
        Property  | Description             | Type | Reqd | Default
        type      | Function type: cosine   | word | yes |
        amplitude | Amplitude               | Function1<scalar> | no | 1
        frequency | Frequency [1/s]         | Function1<scalar> | or period |
        period    | Period [s]              | Function1<scalar> | or frequency |
        scale     | Scale factor (Type)     | Function1<Type> | yes |
        level     | Offset level (Type)     | Function1<Type> | yes |
        t0        | Start time offset       | scalar       | no | 0
    \endtable
 
Note
    For slow oscillations it can be more intuitive to specify the period.
 
SourceFiles
    Cosine.C
 
\*---------------------------------------------------------------------------*/
 
#ifndef Function1Types_Cosine_H
#define Function1Types_Cosine_H
 
#include "Sine.H"
 
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
namespace Foam
{
namespace Function1Types
{
 
/*---------------------------------------------------------------------------*\
                            Class Cosine Declaration
\*---------------------------------------------------------------------------*/
 
template<class Type>
class Cosine
:
    public Function1Types::Sine<Type>
{
public:
 
    // Runtime type information
    TypeName("cosine");
 
 
    // Generated Methods
 
        //- No copy assignment
        void operator=(const Cosine<Type>&) = delete;
 
 
    // Constructors
 
        //- Construct from entry name, dictionary and optional registry
        Cosine
        (
            const word& entryName,
            const dictionary& dict,
            const objectRegistry* obrPtr = nullptr
        )
        :
            Sine<Type>(entryName, dict, obrPtr)
        {}
 
        //- Copy construct
        explicit Cosine(const Cosine<Type>& rhs)
        :
            Sine<Type>(rhs)
        {}
 
 
    //- Destructor
    virtual ~Cosine() = default;
 
 
    // Member Functions
 
        //- Return value for time t
        virtual inline Type value(const scalar t) const
        {
            return Sine<Type>::cosValue(t);
        }
};
 
 
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
} // End namespace Function1Types
} // End namespace Foam
 
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
#endif
 
// ************************************************************************* //