Public Member Functions
	SolarPosition (helios::Context *context_ptr)
	Solar position model default constructor. Initializes location based on the location set in the Context.

	SolarPosition (float UTC_hrs, float latitude_deg, float longitude_deg, helios::Context *context_ptr)
	Solar position model constructor.

helios::Time	getSunriseTime () const
	Get the approximate time of sunrise at the current location.

helios::Time	getSunsetTime () const
	Get the approximate time of sunset at the current location.

float	getSunElevation () const
	Get the current sun elevation angle in radians for the current location. The sun angle is computed based on the current time and date set in the Helios context.

float	getSunZenith () const
	Get the current sun zenithal angle in radians for the current location. The sun angle is computed based on the current time and date set in the Helios context.

float	getSunAzimuth () const
	Get the current sun azimuthal angle in radians for the current location. The sun angle is computed based on the current time and date set in the Helios context.

helios::vec3	getSunDirectionVector () const
	Get a unit vector pointing toward the sun for the current location. The sun angle is computed based on the current time and date set in the Helios context.

helios::SphericalCoord	getSunDirectionSpherical () const
	Get a spherical coordinate vector pointing toward the sun for the current location. The sun angle is computed based on the current time and date set in the Helios context.

void	setSunDirection (const helios::SphericalCoord &sundirection)
	Override solar position calculation based on time in the Context by using a prescribed solar position.

float	getSolarFlux (float pressure_Pa, float temperature_K, float humidity_rel, float turbidity) const
	Get the solar radiation flux perpendicular to the sun direction.

float	getSolarFluxPAR (float pressure_Pa, float temperature_K, float humidity_rel, float turbidity) const
	Get the photosynthetically active (PAR) component of solar radiation flux perpendicular to the sun direction.

float	getSolarFluxNIR (float pressure_Pa, float temperature_K, float humidity_rel, float turbidity) const
	Get the near-infrared (NIR) component of solar radiation flux perpendicular to the sun direction.

float	getDiffuseFraction (float pressure_Pa, float temperature_K, float humidity_rel, float turbidity) const
	Get the fraction of solar radiation flux that is diffuse.

float	getAmbientLongwaveFlux (float temperature_K, float humidity_rel) const
	Calculate the ambient (sky) longwave radiation flux.

float	calibrateTurbidityFromTimeseries (const std::string &timeseries_shortwave_flux_label_Wm2) const
	Calculate the turbidity value based on a timeseries of net radiation measurements.

void	enableCloudCalibration (const std::string &timeseries_shortwave_flux_label_Wm2)
	Enable calibration of solar flux and diffuse fraction when possibility of clouds are present against measured solar flux data.

void	disableCloudCalibration ()
	Disable calibration of solar flux and diffuse fraction for clouds.

Static Public Member Functions
static int	selfTest (int argc=0, char **argv=nullptr)
	Function to perform a self-test of model functions.

Detailed Description

Definition at line 21 of file SolarPosition.h.

Constructor & Destructor Documentation

◆ SolarPosition() [1/2]

SolarPosition::SolarPosition ( helios::Context * context_ptr )

explicit

Solar position model default constructor. Initializes location based on the location set in the Context.

Parameters

[in] context_ptr Pointer to the Helios context

Definition at line 21 of file SolarPosition.cpp.

◆ SolarPosition() [2/2]

SolarPosition::SolarPosition	(	float	UTC_hrs,
		float	latitude_deg,
		float	longitude_deg,
		helios::Context *	context_ptr
	)

Solar position model constructor.

Parameters

[in]	context_ptr	Pointer to the Helios context
[in]	UTC_hrs	Hours from Coordinated Universal Time (UTC) for location of interest. Convention is that UTC is positive moving Westward.
[in]	latitude_deg	Latitude in degrees for location of interest. Convention is latitude is positive for Northern hemisphere.
[in]	longitude_deg	Longitude in degrees for location of interest. Convention is longitude is positive for Western hemisphere.

Definition at line 29 of file SolarPosition.cpp.

Member Function Documentation

◆ calibrateTurbidityFromTimeseries()

float SolarPosition::calibrateTurbidityFromTimeseries ( const std::string & timeseries_shortwave_flux_label_Wm2 ) const

Calculate the turbidity value based on a timeseries of net radiation measurements.

Parameters

[in] timeseries_shortwave_flux_label_Wm2 Label of the timeseries variable in the Helios context that contains the net radiation flux measurements

Returns: Turbidity value

Note: The net radiation flux measurements contained in the timeseries should be global shortwave radiation flux on a horizontal plane in W/m^2. The data should contain at least one day with clear sky conditions.

Definition at line 381 of file SolarPosition.cpp.

◆ disableCloudCalibration()

void SolarPosition::disableCloudCalibration ( )

Disable calibration of solar flux and diffuse fraction for clouds.

Definition at line 431 of file SolarPosition.cpp.

◆ enableCloudCalibration()

void SolarPosition::enableCloudCalibration ( const std::string & timeseries_shortwave_flux_label_Wm2 )

Enable calibration of solar flux and diffuse fraction when possibility of clouds are present against measured solar flux data.

Parameters

[in] timeseries_shortwave_flux_label_Wm2 Label for timeseries data field containing measured total shortwave flux data (W/m^2).

Definition at line 422 of file SolarPosition.cpp.

◆ getAmbientLongwaveFlux()

float SolarPosition::getAmbientLongwaveFlux	(	float	temperature_K,
		float	humidity_rel
	)		const

Calculate the ambient (sky) longwave radiation flux.

Parameters

[in]	temperature_K	Air temperature near the ground surface in Kelvin
[in]	humidity_rel	Air relative humidity near the ground surface

Returns: Ambient longwave flux in W/m^2

Note: The longwave flux model is based on Prata (1996).

Definition at line 354 of file SolarPosition.cpp.

◆ getDiffuseFraction()

float SolarPosition::getDiffuseFraction	(	float	pressure_Pa,
		float	temperature_K,
		float	humidity_rel,
		float	turbidity
	)		const

Get the fraction of solar radiation flux that is diffuse.

Parameters

[in]	pressure_Pa	Atmospheric pressure near ground surface in Pascals
[in]	temperature_K	Air temperature near the ground surface in Kelvin
[in]	humidity_rel	Air relative humidity near the ground surface
[in]	turbidity	Angstrom's aerosol turbidity coefficient

Returns: Fraction of global radiation that is diffuse

Definition at line 213 of file SolarPosition.cpp.

◆ getSolarFlux()

float SolarPosition::getSolarFlux	(	float	pressure_Pa,
		float	temperature_K,
		float	humidity_rel,
		float	turbidity
	)		const

Get the solar radiation flux perpendicular to the sun direction.

Parameters

[in]	pressure_Pa	Atmospheric pressure near ground surface in Pascals
[in]	temperature_K	Air temperature near the ground surface in Kelvin
[in]	humidity_rel	Air relative humidity near the ground surface
[in]	turbidity	Angstrom's aerosol turbidity coefficient

Note: The flux given by this function is the flux normal to the sun direction. To get the flux on a horizontal surface, multiply the returned value by cos(theta), where theta can be found by calling the getSunZenith() function.; The solar flux model is based on Gueymard (2008).

Returns: Global solar radiation flux NORMAL TO THE SUN DIRECTION in W/m^2

Definition at line 185 of file SolarPosition.cpp.

◆ getSolarFluxNIR()

float SolarPosition::getSolarFluxNIR	(	float	pressure_Pa,
		float	temperature_K,
		float	humidity_rel,
		float	turbidity
	)		const

Get the near-infrared (NIR) component of solar radiation flux perpendicular to the sun direction.

Parameters

[in]	pressure_Pa	Atmospheric pressure near ground surface in Pascals
[in]	temperature_K	Air temperature near the ground surface in Kelvin
[in]	humidity_rel	Air relative humidity near the ground surface
[in]	turbidity	Angstrom's aerosol turbidity coefficient

Note: The flux given by this function is the flux normal to the sun direction. To get the flux on a horizontal surface, multiply the returned value by cos(theta), where theta can be found by calling the getSunZenith() function.; The solar flux model is based on Gueymard (2008).

Returns: Global solar radiation flux NORMAL TO THE SUN DIRECTION in W/m^2

Definition at line 204 of file SolarPosition.cpp.

◆ getSolarFluxPAR()

float SolarPosition::getSolarFluxPAR	(	float	pressure_Pa,
		float	temperature_K,
		float	humidity_rel,
		float	turbidity
	)		const

Get the photosynthetically active (PAR) component of solar radiation flux perpendicular to the sun direction.

Parameters

[in]	pressure_Pa	Atmospheric pressure near ground surface in Pascals
[in]	temperature_K	Air temperature near the ground surface in Kelvin
[in]	humidity_rel	Air relative humidity near the ground surface
[in]	turbidity	Angstrom's aerosol turbidity coefficient

Note: The flux given by this function is the flux normal to the sun direction. To get the flux on a horizontal surface, multiply the returned value by cos(theta), where theta can be found by calling the getSunZenith() function.; The solar flux model is based on Gueymard (2008).

Returns: Global solar radiation flux NORMAL TO THE SUN DIRECTION in W/m^2

Definition at line 195 of file SolarPosition.cpp.

◆ getSunAzimuth()

float SolarPosition::getSunAzimuth ( ) const

Get the current sun azimuthal angle in radians for the current location. The sun angle is computed based on the current time and date set in the Helios context.

Definition at line 150 of file SolarPosition.cpp.

◆ getSunDirectionSpherical()

SphericalCoord SolarPosition::getSunDirectionSpherical ( ) const

Get a spherical coordinate vector pointing toward the sun for the current location. The sun angle is computed based on the current time and date set in the Helios context.

Definition at line 170 of file SolarPosition.cpp.

◆ getSunDirectionVector()

vec3 SolarPosition::getSunDirectionVector ( ) const

Get a unit vector pointing toward the sun for the current location. The sun angle is computed based on the current time and date set in the Helios context.

Definition at line 160 of file SolarPosition.cpp.

◆ getSunElevation()

float SolarPosition::getSunElevation ( ) const

Get the current sun elevation angle in radians for the current location. The sun angle is computed based on the current time and date set in the Helios context.

Definition at line 130 of file SolarPosition.cpp.

◆ getSunriseTime()

Time SolarPosition::getSunriseTime ( ) const

Get the approximate time of sunrise at the current location.

Definition at line 94 of file SolarPosition.cpp.

◆ getSunsetTime()

Time SolarPosition::getSunsetTime ( ) const

Get the approximate time of sunset at the current location.

Definition at line 112 of file SolarPosition.cpp.

◆ getSunZenith()

float SolarPosition::getSunZenith ( ) const

Get the current sun zenithal angle in radians for the current location. The sun angle is computed based on the current time and date set in the Helios context.

Definition at line 140 of file SolarPosition.cpp.

◆ selfTest()

int SolarPosition::selfTest	(	int	argc = `0`,
		char **	argv = `nullptr`
	)

static

Function to perform a self-test of model functions.

Definition at line 232 of file selfTest.cpp.

◆ setSunDirection()

void SolarPosition::setSunDirection ( const helios::SphericalCoord & sundirection )

Override solar position calculation based on time in the Context by using a prescribed solar position.

Parameters

[in] sundirection SphericalCoord giving the direction of the sun

Definition at line 180 of file SolarPosition.cpp.

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

plugins/solarposition/include/SolarPosition.h
plugins/solarposition/src/SolarPosition.cpp
plugins/solarposition/tests/selfTest.cpp

Public Member Functions

Static Public Member Functions

Detailed Description

Constructor & Destructor Documentation

◆ SolarPosition() [1/2]

◆ SolarPosition() [2/2]

Member Function Documentation

◆ calibrateTurbidityFromTimeseries()

◆ disableCloudCalibration()

◆ enableCloudCalibration()

◆ getAmbientLongwaveFlux()

◆ getDiffuseFraction()

◆ getSolarFlux()

◆ getSolarFluxNIR()

◆ getSolarFluxPAR()

◆ getSunAzimuth()

◆ getSunDirectionSpherical()

◆ getSunDirectionVector()

◆ getSunElevation()

◆ getSunriseTime()

◆ getSunsetTime()

◆ getSunZenith()

◆ selfTest()

◆ setSunDirection()