CECorrections class handles downloading and retrieving corrections from the IERS bulletins. Current corrections obtainable:

DUT1
X/Y polar motions

The way this is done is by downloading the corrections data on the fly from: http://maia.usno.navy.mil/ser7/finals2000A.all The downloaded file will be stored locally to prevent the need to re-download it every time it is needed in the future.

IMPORTANT NOTE: These correction values should only be accessed through the CppEphem namespace, and not by directly querying this class. This prevents creating multiple CECorrections objects that could be resource intensive.

Definition at line 28 of file CECorrections.h.

Public Member Functions
	CECorrections ()
	Constructor for coordinate corrections object. More...

	CECorrections (const CECorrections &other)
	Copy constructor. More...

double	deps (const double &mjd) const
	Return the offset in obliquity correction parameter (radians) More...

double	dpsi (const double &mjd) const
	Return the offset in longitude correction parameter (radians) More...

double	dut1 (const double &mjd) const
	Return the DUT1 correction parameter (represents UT1 - UTC in seconds) More...

std::string	NutationFile (void) const
	Returns the name of the nutation corrections file. More...

CECorrections &	operator= (const CECorrections &other)
	Overloaded assignment operator. More...

void	SetInterp (bool set_interp)
	Defines that the correction values should be interpolated. More...

void	SetNutationFile (const std::string &filename)
	Sets the name of the nutation corrections file. More...

void	SetTtUt1HistFile (const std::string &filename)
	Sets the name of the historic values TT-UT1 corrections file. More...

void	SetTtUt1PredFile (const std::string &filename)
	Sets the name of the predicted values TT-UT1 corrections file. More...

double	ttut1 (const double &mjd) const
	Return the TT-UT1 correction at a given date (in seconds) More...

std::string	TtUt1HistFile (void) const
	Returns the name of the historic TT-UT1 corrections file. More...

std::string	TtUt1PredFile (void) const
	Returns the name of the precited TT-UT1 corrections file. More...

double	xpolar (const double &mjd) const
	Return the x-polar motion correction parameter (radians) More...

double	ypolar (const double &mjd) const
	Return the y-polar motion correction parameter (radians) More...

virtual	~CECorrections ()

Private Member Functions
void	copy_members (const CECorrections &other)
	Copy data members from another object. More...

bool	DownloadTable (const std::string &filename, const std::string &url) const
	Downloads the IERS earth orientation correction parameters. More...

void	free_members (void)
	Free data member objects. More...

void	init_members (void)
	Initialize data members. More...

double	InterpValue (const double &x, const double &x0, const double &x1, const double &y0, const double &y1) const
	Return the interpolated value at a given x value between two known values. More...

std::ifstream	LoadFile (const std::string &filename, const std::string &url) const
	Initialize data members. More...

bool	LoadNutation (void) const
	Loads the IERS earth orientation correction parameters. More...

bool	LoadTtUt1 (void) const
	Loads the TT-UT1 correction values. More...

void	UpdateNutationCache (const double &mjd) const
	Recompute cached values of nutation valeus if necessary. More...

void	UpdateTtUt1Cache (const double &mjd) const
	Recompute cached values of nutation valeus if necessary. More...

Private Attributes
double	cache_nut_deps_

double	cache_nut_dpsi_

double	cache_nut_dut1_

double	cache_nut_mjd_

double	cache_nut_xp_

double	cache_nut_yp_

double	cache_ttut1_delt_

double	cache_ttut1_mjd_

bool	interp_

std::vector< double >	nutation_deps_

std::vector< double >	nutation_dpsi_

std::vector< double >	nutation_dut1_

std::string	nutation_file_
	File for nutation corrections. More...

std::vector< int >	nutation_mjd_

std::vector< double >	nutation_xp_

std::vector< double >	nutation_yp_

std::vector< double >	ttut1_delt_

std::string	ttut1_file_hist_
	File for historic TT-UT1 corrections. More...

std::string	ttut1_file_pred_
	File for predicted TT-UT1 corrections. More...

std::vector< double >	ttut1_mjd_

#include <CECorrections.h>

Constructor & Destructor Documentation

◆ CECorrections() [1/2]

CECorrections::CECorrections ( )

Constructor for coordinate corrections object.

Definition at line 58 of file CECorrections.cpp.

◆ CECorrections() [2/2]

CECorrections::CECorrections ( const CECorrections & other )

Copy constructor.

Definition at line 67 of file CECorrections.cpp.

◆ ~CECorrections()

virtual CECorrections::~CECorrections ( )

inlinevirtual

Definition at line 50 of file CECorrections.h.

Member Function Documentation

◆ copy_members()

void CECorrections::copy_members ( const CECorrections & other )

private

Copy data members from another object.

Parameters

[in] other CECorrections object to be copied

Definition at line 260 of file CECorrections.cpp.

◆ deps()

double CECorrections::deps ( const double & mjd ) const

Return the offset in obliquity correction parameter (radians)

Parameters

[in] mjd Modified Julian date

Returns: Obliquity correction parameter (radians)

Definition at line 127 of file CECorrections.cpp.

◆ DownloadTable()

bool CECorrections::DownloadTable	(	const std::string &	filename,
		const std::string &	url
	)		const

private

Downloads the IERS earth orientation correction parameters.

Returns: Whether or not the download was successful

Definition at line 360 of file CECorrections.cpp.

◆ dpsi()

double CECorrections::dpsi ( const double & mjd ) const

Return the offset in longitude correction parameter (radians)

Parameters

[in] mjd Modified Julian date

Returns: longitude offset correction parameter (radians)

Definition at line 143 of file CECorrections.cpp.

◆ dut1()

double CECorrections::dut1 ( const double & mjd ) const

Return the DUT1 correction parameter (represents UT1 - UTC in seconds)

Parameters

[in] mjd Modified Julian date

Returns: DUT1 correction parameter (represents UT1 - UTC in seconds)

Definition at line 79 of file CECorrections.cpp.

◆ free_members()

void CECorrections::free_members ( void )

private

Free data member objects.

Definition at line 239 of file CECorrections.cpp.

◆ init_members()

void CECorrections::init_members ( void )

private

Initialize data members.

Definition at line 289 of file CECorrections.cpp.

◆ InterpValue()

double CECorrections::InterpValue	(	const double &	x,
		const double &	x0,
		const double &	x1,
		const double &	y0,
		const double &	y1
	)		const

private

Return the interpolated value at a given x value between two known values.

Parameters

[in]	x	Desired position for interpolation
[in]	x0	Lower position where value is known
[in]	x1	Upper position where value is known
[in]	y0	Known value at position `x0`
[in]	y1	Known value at position `x1`

Returns: Obliquity correction parameter

Definition at line 707 of file CECorrections.cpp.

◆ LoadFile()

std::ifstream CECorrections::LoadFile	(	const std::string &	filename,
		const std::string &	url
	)		const

private

Initialize data members.

Definition at line 324 of file CECorrections.cpp.

◆ LoadNutation()

bool CECorrections::LoadNutation ( void ) const

private

Loads the IERS earth orientation correction parameters.

Returns: Whether or not the load was successful

Definition at line 404 of file CECorrections.cpp.

◆ LoadTtUt1()

bool CECorrections::LoadTtUt1 ( void ) const

private

Loads the TT-UT1 correction values.

Returns: Whether or not the load was successful

Definition at line 494 of file CECorrections.cpp.

◆ NutationFile()

std::string CECorrections::NutationFile ( void ) const

inline

Returns the name of the nutation corrections file.

Returns: Nutation corrections filename

Definition at line 107 of file CECorrections.h.

◆ operator=()

CECorrections & CECorrections::operator= ( const CECorrections & other )

Overloaded assignment operator.

Parameters

[in] other CECorrections object to be copied

Returns: Reference to this object post-assignment

Definition at line 175 of file CECorrections.cpp.

◆ SetInterp()

void CECorrections::SetInterp ( bool set_interp )

Defines that the correction values should be interpolated.

Parameters

[in] set_interp New interpolation boolean

Definition at line 224 of file CECorrections.cpp.

◆ SetNutationFile()

void CECorrections::SetNutationFile ( const std::string & filename )

Sets the name of the nutation corrections file.

Parameters

[in] filename Filename to read/write corrections from/to

Definition at line 191 of file CECorrections.cpp.

◆ SetTtUt1HistFile()

void CECorrections::SetTtUt1HistFile ( const std::string & filename )

Sets the name of the historic values TT-UT1 corrections file.

Parameters

[in] filename Filename to read/write corrections from/to

Definition at line 202 of file CECorrections.cpp.

◆ SetTtUt1PredFile()

void CECorrections::SetTtUt1PredFile ( const std::string & filename )

Sets the name of the predicted values TT-UT1 corrections file.

Parameters

[in] filename Filename to read/write corrections from/to

Definition at line 213 of file CECorrections.cpp.

◆ ttut1()

double CECorrections::ttut1 ( const double & mjd ) const

Return the TT-UT1 correction at a given date (in seconds)

Parameters

[in] mjd Modified Julian date

Returns: TT-UT1 offset correction parameter at a given MJD (seconds)

Definition at line 159 of file CECorrections.cpp.

◆ TtUt1HistFile()

std::string CECorrections::TtUt1HistFile ( void ) const

inline

Returns the name of the historic TT-UT1 corrections file.

Returns: Historic TT-UT1 corrections filename

Definition at line 119 of file CECorrections.h.

◆ TtUt1PredFile()

std::string CECorrections::TtUt1PredFile ( void ) const

inline

Returns the name of the precited TT-UT1 corrections file.

Returns: Predicted TT-UT1 corrections filename

Definition at line 131 of file CECorrections.h.

◆ UpdateNutationCache()

void CECorrections::UpdateNutationCache ( const double & mjd ) const

private

Recompute cached values of nutation valeus if necessary.

Parameters

[in] mjd Modified Julian date for lookup

Definition at line 590 of file CECorrections.cpp.

◆ UpdateTtUt1Cache()

void CECorrections::UpdateTtUt1Cache ( const double & mjd ) const

private

Recompute cached values of nutation valeus if necessary.

Parameters

[in] mjd Modified Julian date for lookup

Definition at line 654 of file CECorrections.cpp.

◆ xpolar()

double CECorrections::xpolar ( const double & mjd ) const

Return the x-polar motion correction parameter (radians)

Parameters

[in] mjd Modified Julian date

Returns: x-polar motion correction parameter (radians)

Definition at line 95 of file CECorrections.cpp.

◆ ypolar()

double CECorrections::ypolar ( const double & mjd ) const

Return the y-polar motion correction parameter (radians)

Parameters

[in] mjd Modified Julian date

Returns: y-polar motion correction parameter (radians)

Definition at line 111 of file CECorrections.cpp.

Member Data Documentation

◆ cache_nut_deps_

double CECorrections::cache_nut_deps_

mutableprivate

Definition at line 112 of file CECorrections.h.

◆ cache_nut_dpsi_

double CECorrections::cache_nut_dpsi_

mutableprivate

Definition at line 113 of file CECorrections.h.

◆ cache_nut_dut1_

double CECorrections::cache_nut_dut1_

mutableprivate

Definition at line 109 of file CECorrections.h.

◆ cache_nut_mjd_

double CECorrections::cache_nut_mjd_

mutableprivate

Definition at line 108 of file CECorrections.h.

◆ cache_nut_xp_

double CECorrections::cache_nut_xp_

mutableprivate

Definition at line 110 of file CECorrections.h.

◆ cache_nut_yp_

double CECorrections::cache_nut_yp_

mutableprivate

Definition at line 111 of file CECorrections.h.

◆ cache_ttut1_delt_

double CECorrections::cache_ttut1_delt_

mutableprivate

Definition at line 115 of file CECorrections.h.

◆ cache_ttut1_mjd_

double CECorrections::cache_ttut1_mjd_

mutableprivate

Definition at line 114 of file CECorrections.h.

◆ interp_

bool CECorrections::interp_

private

Definition at line 104 of file CECorrections.h.

◆ nutation_deps_

std::vector<double> CECorrections::nutation_deps_

mutableprivate

Definition at line 95 of file CECorrections.h.

◆ nutation_dpsi_

std::vector<double> CECorrections::nutation_dpsi_

mutableprivate

Definition at line 96 of file CECorrections.h.

◆ nutation_dut1_

std::vector<double> CECorrections::nutation_dut1_

mutableprivate

Definition at line 92 of file CECorrections.h.

◆ nutation_file_

std::string CECorrections::nutation_file_

mutableprivate

File for nutation corrections.

Definition at line 86 of file CECorrections.h.

◆ nutation_mjd_

std::vector<int> CECorrections::nutation_mjd_

mutableprivate

Definition at line 91 of file CECorrections.h.

◆ nutation_xp_

std::vector<double> CECorrections::nutation_xp_

mutableprivate

Definition at line 93 of file CECorrections.h.

◆ nutation_yp_

std::vector<double> CECorrections::nutation_yp_

mutableprivate

Definition at line 94 of file CECorrections.h.

◆ ttut1_delt_

std::vector<double> CECorrections::ttut1_delt_

mutableprivate

Definition at line 99 of file CECorrections.h.

◆ ttut1_file_hist_

std::string CECorrections::ttut1_file_hist_

mutableprivate

File for historic TT-UT1 corrections.

Definition at line 87 of file CECorrections.h.

◆ ttut1_file_pred_

std::string CECorrections::ttut1_file_pred_

mutableprivate

File for predicted TT-UT1 corrections.

Definition at line 88 of file CECorrections.h.

◆ ttut1_mjd_

std::vector<double> CECorrections::ttut1_mjd_

mutableprivate

Definition at line 98 of file CECorrections.h.

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

cppephem/include/CECorrections.h
cppephem/src/CECorrections.cpp

Public Member Functions

Private Member Functions

Private Attributes

Constructor & Destructor Documentation

◆ CECorrections() [1/2]

◆ CECorrections() [2/2]

◆ ~CECorrections()

Member Function Documentation

◆ copy_members()

◆ deps()

◆ DownloadTable()

◆ dpsi()

◆ dut1()

◆ free_members()

◆ init_members()

◆ InterpValue()

◆ LoadFile()

◆ LoadNutation()

◆ LoadTtUt1()

◆ NutationFile()

◆ operator=()

◆ SetInterp()

◆ SetNutationFile()

◆ SetTtUt1HistFile()

◆ SetTtUt1PredFile()

◆ ttut1()

◆ TtUt1HistFile()

◆ TtUt1PredFile()

◆ UpdateNutationCache()

◆ UpdateTtUt1Cache()

◆ xpolar()

◆ ypolar()

Member Data Documentation

◆ cache_nut_deps_

◆ cache_nut_dpsi_

◆ cache_nut_dut1_

◆ cache_nut_mjd_

◆ cache_nut_xp_

◆ cache_nut_yp_

◆ cache_ttut1_delt_

◆ cache_ttut1_mjd_

◆ interp_

◆ nutation_deps_

◆ nutation_dpsi_

◆ nutation_dut1_

◆ nutation_file_

◆ nutation_mjd_

◆ nutation_xp_

◆ nutation_yp_

◆ ttut1_delt_

◆ ttut1_file_hist_

◆ ttut1_file_pred_

◆ ttut1_mjd_