Hanning.H

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    This file is part of OpenFOAM.
 
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Class
    Foam::windowModels::Hanning
 
Description
    Hanning window
 
    The window is described by the function
    \f[
        wf = (1 - \alpha) - \alpha cos(2 \pi t/m);
    \f]
 
    Where:
    \vartable
        \alpha  | Coefficient with a default value of 0.5
        t       | time
        m       | window width
    \endvartable
 
    The window can be further manipulated by the controls:
    - \c symmetric: force the window to be symmetric
    - \c extended: extend the window by 1 element at start and end to produce
      non-zero values at the start and end positions.  Note: window is
      normalised to preserve energy content
 
SourceFiles
    Hanning.C
 
\*---------------------------------------------------------------------------*/
 
#ifndef Hanning_H
#define Hanning_H
 
#include "autoPtr.H"
#include "runTimeSelectionTables.H"
#include "windowModel.H"
 
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
namespace Foam
{
namespace windowModels
{
 
/*---------------------------------------------------------------------------*\
                           Class Hanning Declaration
\*---------------------------------------------------------------------------*/
 
class Hanning
:
    public windowModel
{
 
protected:
 
    // Protected Member Data
 
        //- Symmetric switch
        bool symmetric_;
 
        //- Extended switch
        bool extended_;
 
        //- Window coefficient, default = 0.5
        scalar alpha_;
 
 
public:
 
    //- Runtime type information
    TypeName("Hanning");
 
 
    //- Construct from dictionary
    Hanning(const dictionary& dict, const label nSamples);
 
    //- Destructor
    virtual ~Hanning() = default;
 
 
    // Public Member Functions
 
        //- Return the symmetric flag
        bool symmetric() const;
 
        //- Return the extended flag
        bool extended() const;
 
        //- Return the window coefficient
        scalar alpha() const;
};
 
 
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
} // End namespace windowModels
} // End namespace Foam
 
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
#endif
 
// ************************************************************************* //