Represents a wave field.

#include <WaveEnergySpectrum.h>

Inheritance diagram for marenv::wave::WaveEnergySpectrum:

Collaboration diagram for marenv::wave::WaveEnergySpectrum:

Classes
struct	SpectrumParameters
	The parameters defining a certain wave field. More...

Public Types
enum class	DirectionSpectrum { None = 0 , CosineSquared }
	Shape function for the direction spectrum. More...

enum class	DirectionBinning { Random , Sequential }
	Methods for realisation of direction spectrum. More...

enum class	FrequencyBinning { EqualEnergy , EqualSqrtEnergy }
	Methods for dividing a spectrum in discrete frequencies. More...

Public Member Functions
	WaveEnergySpectrum (const SpectrumParameters &spectrumParameters, int numWaves, uint32_t randomSeed)

std::shared_ptr< WaveComponents >	GetWaveComponents ()

Protected Types
using	NormalizedProbabilityDistribution = double(WaveEnergySpectrum::*)(const double)
	Defines the type of a normalized probability distribution function.

Protected Member Functions
void	CalcWaveDirections (calc::LcgRandom &random)

double	IntegrateSpectrum (double omegaLow, double omegaHigh, double step) const

double	BinFrequency (double omegaLow, double omegaHigh, double step) const

std::vector< double >	CalcBinEdges () const

void	CalcWaveFrequencies ()

void	CalcCalmSeaFrequencies ()
	Calculates the frequencies of a calm sea (Hs = 0): those of Hs = 1, with zero energy and amplitude.

double	CosPower (double theta) const

double	SpectralEnergy (double omega) const

double	JONSWAP (double omega) const

double	Issc (double omega) const

Protected Attributes
SpectrumParameters	m_param
	Wave spectrum parameters.

Member Enumeration Documentation

◆ DirectionBinning

enum class marenv::wave::WaveEnergySpectrum::DirectionBinning

strong

Enumerator
Random	Random distribution according to the direction spectrum.
Sequential	Higher energies in main direction.

◆ DirectionSpectrum

enum class marenv::wave::WaveEnergySpectrum::DirectionSpectrum

strong

Enumerator
CosineSquared	The function is of the form cos(theta)^n.

◆ FrequencyBinning

enum class marenv::wave::WaveEnergySpectrum::FrequencyBinning

strong

Enumerator
EqualEnergy	Each wave component has the same energy.
EqualSqrtEnergy	Each wave component has the same \( \int_{\omega_k}^{\omega_{k+1}} S(\omega)\, d\omega \).

Constructor & Destructor Documentation

◆ WaveEnergySpectrum()

marenv::wave::WaveEnergySpectrum::WaveEnergySpectrum	(	const SpectrumParameters &	spectrumParameters,
		int	numWaves,
		uint32_t	randomSeed
	)

Constructor.

Parameters

[in]	spectrumParameters	Spectrum parameters.
[in]	numWaves	Number of waves to construct from the spectrum.
[in]	randomSeed	The random seed to use.

Exceptions

std::invalid_argument	for a non-finite or negative Hs, a non-finite or non-positive T1, a non-finite Theta, frequency limits that are not finite with 0 <= lower < upper, and a negative numWaves (0 gives a sea state without components).
std::runtime_error	if the spectrum is NaN. Hs = 0 is legal: a calm sea, with the components of the frequency grid and zero amplitude.

Member Function Documentation

◆ BinFrequency()

double marenv::wave::WaveEnergySpectrum::BinFrequency	(	double	omegaLow,
		double	omegaHigh,
		double	step
	)		const

protected

Frequency of a bin: the energy-weighted mean \( \int \omega S(\omega)\, d\omega / \int S(\omega)\, d\omega \) over [omegaLow, omegaHigh] (owner ruling D50), both integrals by the same composite Simpson rule as IntegrateSpectrum().

Parameters

[in]	omegaLow	Lower frequency limit of the bin.
[in]	omegaHigh	Upper frequency limit of the bin.
[in]	step	The widest panel to use, as for IntegrateSpectrum().

Returns: The weighted mean frequency. A bin of zero width or zero energy has no weighting: the midpoint is returned.

◆ CalcBinEdges()

std::vector< double > marenv::wave::WaveEnergySpectrum::CalcBinEdges ( ) const

protected

The edges of the frequency bins for the binning mode: numWaves + 1 ascending values, the first and the last being the ends of the frequency range. Needs a spectrum with energy (Hs > 0).

◆ CalcWaveDirections()

void marenv::wave::WaveEnergySpectrum::CalcWaveDirections ( calc::LcgRandom & random )

protected

Calculates wave directions according to the specified spectrum parameters.

Parameters

[in,out] random The generator of the whole spectrum. Directions and phases are drawn from it in turn, so the two are independent.

◆ CalcWaveFrequencies()

void marenv::wave::WaveEnergySpectrum::CalcWaveFrequencies ( )

protected

Calculates frequencies of each wave component.

The bins cover the whole cumulative distribution, from probability 0 to 1. The energy of a bin is the integral of the spectrum over the bin, so the energies add up to the spectrum energy \( m_0 \) over the frequency range and \( H_s = 4\sqrt{m_0} \) is realised for any number of components. The frequency of a bin is its energy-weighted mean frequency (BinFrequency()), for both binning modes; the wave number follows from it.

◆ CosPower()

double marenv::wave::WaveEnergySpectrum::CosPower ( double theta ) const

protected

Computes \( \cos^{\text{cosinePower}}(\theta) \)

Parameters

[in] theta The wave direction relative to the main direction.

Returns: The cosine power of theta;

◆ GetWaveComponents()

std::shared_ptr< WaveComponents > marenv::wave::WaveEnergySpectrum::GetWaveComponents ( )

Get all wave components.

Returns: All wave components.

◆ IntegrateSpectrum()

double marenv::wave::WaveEnergySpectrum::IntegrateSpectrum	(	double	omegaLow,
		double	omegaHigh,
		double	step
	)		const

protected

Integral of the spectrum over [omegaLow, omegaHigh] (Simpson's rule).

Parameters

[in]	omegaLow	Lower frequency limit.
[in]	omegaHigh	Upper frequency limit.
[in]	step	The widest panel to use.

Returns: The energy of the spectrum in the band, \( \int S(\omega)\, d\omega \).

◆ Issc()

double marenv::wave::WaveEnergySpectrum::Issc ( double omega ) const

protected

Calculates the ISSC spectrum energy for a wave frequency.

Parameters

[in] omega The wave frequency

Returns: The ISSC spectrum energy for the given wave frequency.

◆ JONSWAP()

double marenv::wave::WaveEnergySpectrum::JONSWAP ( double omega ) const

protected

Calculates the JONSWAP spectrum energy for a wave frequency.

Parameters

[in] omega The wave frequency

Returns: The ISSC JONSWAP energy for the given wave frequency.

◆ SpectralEnergy()

double marenv::wave::WaveEnergySpectrum::SpectralEnergy ( double omega ) const

protected

Calculates the spectrum energy for a wave frequency.

Parameters

[in] omega The wave frequency

Returns: The spectrum energy for the given wave frequency.

The documentation for this class was generated from the following file:

webfhsim/reloadrepos/marenv/include/marenv/wave/WaveEnergySpectrum.h

Classes

Public Types

Public Member Functions

Protected Types

Protected Member Functions

Protected Attributes

Member Enumeration Documentation

◆ DirectionBinning

◆ DirectionSpectrum

◆ FrequencyBinning

Constructor & Destructor Documentation

◆ WaveEnergySpectrum()

Member Function Documentation

◆ BinFrequency()

◆ CalcBinEdges()

◆ CalcWaveDirections()

◆ CalcWaveFrequencies()

◆ CosPower()

◆ GetWaveComponents()

◆ IntegrateSpectrum()

◆ Issc()

◆ JONSWAP()

◆ SpectralEnergy()