WXP::Gvar Class Reference

This class manages GVAR GOES satellite image navigation. More...

#include "../include/Gvar.h"

Public Member Functions
int	initConstants (int nadnsc, int nadnsi, int nadewc, int nadewi)
int	initParams ()
int	instMatrix (Attitude att, double a[3][3], double at[3][3])
int	getSubPoint (EarthPoint &ept)
float	getScanDelta ()
float	getElevDelta ()
int	tran (SatPoint &spt, SatAngle &sa)
int	tran (SatAngle &sa, SatPoint &spt)
int	tran (SatPoint &spt, EarthPoint &ept)
int	tran (EarthPoint &ept, SatPoint &spt)
int	tran (SatAngle &sa, EarthPoint &ept)
int	tran (EarthPoint &ept, SatAngle &sa)

Static Public Member Functions
static double	epochTime (DateVal dv)
static double	epochTime (unsigned int dmy, unsigned int smh)
static int	setAttitudeAngle (int *data, AttitudeAngle &param)
static double	adjustAttitude (AttitudeAngle &parms, double sol_ang, double exp_tim)

Static Public Attributes
static const double	RADE_EQUA = 6378.388
static const double	RADE_POLE = 6356.912
static const double	RADE_MEAN = 6371.221
static const double	SOLAR_YR = 365.24219879
static const double	SIDER_YR = 366.24219879
static const double	SOLSID = (SIDER_YR/SOLAR_YR)
static const int	REF_DATE = 90001
static const int	REF_TIME = 171537
static const double	PREC_VER_EQ = 25781.
static const double	OBLIQ_ECLIP = 23.45
static const double	NOMORB = 42164.365
static const double	REQ = 6378.137
static const double	RPL = 6356.7533
static const double	REQRPL2 = ((REQ*REQ)/(RPL*RPL))
static const double	FER = (RPL/REQ)
static const double	FER2 = (1-RPL/REQ)
static const double	REQRPL3 = (REQRPL2-1)
static const double	REQRPL4 = (FER*FER*FER*FER-1)

Friends
class	AreaFile

Detailed Description

This class manages GVAR GOES satellite image navigation.

Author

Dan Vietor

Member Function Documentation

adjustAttitude()

double Gvar::adjustAttitude ( AttitudeAngle &  parms, double  sol_ang, double  exp_time  )

static

Calculates attitude and misalignment attributes

Parameters

parms	Attitude angle parameters
sol_ang	Solar orbit angle
exp_time	Exponential time delay from Epoch (minutes)

Returns

Attitude angle

References WXP::MonoSinus::mord, WXP::MonoSinus::ord, and WXP::MonoSinus::sinus.

Referenced by initParams().

epochTime() [1/2]

double Gvar::epochTime ( DateVal  dv )

static

Computes Epoch time from date info

Parameters

dv	The date to use

Returns

Epoch time in minutes since 1/1/1950

References WXP::DateVal::day, WXP::DateVal::hour, WXP::DateVal::min, WXP::DateVal::sec, and WXP::DateVal::year.

Referenced by epochTime(), and WXP::AreaFile::readHeader().

epochTime() [2/2]

double Gvar::epochTime ( unsigned int  hdy, unsigned int  smh  )

static

Computes Epoch time from date info

Parameters

hdy	Hour/Day/Year coded value
smh	Second/Minute/Hour coded value

Returns

Epoch time in minutes since 1/1/1950

References WXP::DateVal::day, epochTime(), WXP::DateVal::hour, WXP::DateVal::min, WXP::DateVal::sec, and WXP::DateVal::year.

getElevDelta()

float Gvar::getElevDelta

(

)

Returns elevation distance between sampling lines

Returns

Elevation scaling

Referenced by WXP::AreaFile::calcDomain().

getScanDelta()

float Gvar::getScanDelta

(

)

Returns scan line distance between sampling points

Returns

Scan scaling

Referenced by WXP::AreaFile::calcDomain().

getSubPoint()

int Gvar::getSubPoint

(

EarthPoint &

ept

)

Returns satellite subpoint location

Return values

ept	Returned earth location

References WXP::EarthPoint::lat, and WXP::EarthPoint::lon.

initConstants()

int Gvar::initConstants	(	int	nadnsc,
		int	nadnsi,
		int	nadewc,
		int	nadewi
	)

Initializes the constants

Parameters

nadnsc	Nadir north south scale correction
nadnsi	Nadir north south offset correction
nadewc	Nadir east west scale correction
nadewi	Nadir east west offset correction

Referenced by WXP::AreaFile::readHeader().

initParams()

int Gvar::initParams

(

)

Computes basic parameters from input data

References adjustAttitude(), instMatrix(), WXP::Const::RDC, WXP::Angle::set(), WXP::Point2::x, WXP::Point2::y, and WXP::Point2::z.

Referenced by WXP::AreaFile::readHeader().

instMatrix()

int Gvar::instMatrix	(	Attitude	att,
		double	a[3][3],
		double	at[3][3]
	)

Calculates instrument to earth coordinate transformation matrix

Parameters

att	Satellite attitude
a	Spacecraft to ECEF coordinates transformation matrix

Return values

at	Instrument to ECEF coordinates transformation matrix

Referenced by initParams().

setAttitudeAngle()

int Gvar::setAttitudeAngle ( int *  data, AttitudeAngle &  param  )

static

Set attitude angle data from coded input

Parameters

data	Raw coded data

Return values

param

Output attitude data

References WXP::MonoSinus::mord, WXP::MonoSinus::ord, and WXP::MonoSinus::sinus.

Referenced by WXP::AreaFile::readHeader().

tran() [1/6]

int Gvar::tran	(	EarthPoint &	ept,
		SatAngle &	sa
	)

Converts earth location to satellite angle

Parameters

ept	Earth location

Return values

sa	Satellite angle

Returns

1 = success, 0 = point invisible

References WXP::Const::DRC, WXP::EarthPoint::lat, WXP::EarthPoint::lon, WXP::Const::MISS, WXP::Point2::x, WXP::Point2::y, and WXP::Point2::z.

tran() [2/6]

int Gvar::tran	(	EarthPoint &	ept,
		SatPoint &	spt
	)

Converts earth location to satellite point

Parameters

ept	Earth location

Return values

spt	Point on image

Returns

1 = success, 0 = point invisible

References WXP::EarthPoint::lat, WXP::Const::MISS, and tran().

tran() [3/6]

int Gvar::tran	(	SatAngle &	sa,
		EarthPoint &	ept
	)

Converts satellite angle to earth location

Parameters

sa	Satellite angle

Return values

ept	Earth location

Returns

1 = success, 0 = point invisible

References WXP::EarthPoint::lat, WXP::EarthPoint::lon, WXP::Const::MISS, WXP::Const::RDC, WXP::Angle::set(), WXP::Point2::set(), WXP::Point2::x, WXP::Point2::y, and WXP::Point2::z.

tran() [4/6]

int Gvar::tran	(	SatAngle &	sa,
		SatPoint &	spt
	)

Converts satellite angle to satellite point

Parameters

sa	Satellite angle

Return values

spt	Point on image

tran() [5/6]

int Gvar::tran	(	SatPoint &	spt,
		EarthPoint &	ept
	)

Converts satellite point to earth location

Parameters

spt	Point on image

Return values

ept	Earth location

Returns

1 = success, 0 = point invisible

References tran().

tran() [6/6]

int Gvar::tran	(	SatPoint &	spt,
		SatAngle &	sa
	)

Converts satellite point to satellite angles

Parameters

spt	Point on image

Return values

sa	Satellite angle

Referenced by WXP::AreaFile::calcDomain(), tran(), and tran().

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

• Gvar.h
• Gvar.cc