QgsProjectionFactors Class Reference

Contains various cartographic properties, such as scale factors, angular distortion and meridian convergence. More...

#include <qgsprojectionfactors.h>

Public Member Functions
double	angularDistortion () const
	Angular distortion at coordinate (λ,ϕ).
double	arealScale () const
	Areal scale factor at coordinate (λ,ϕ).
double	dxDlam () const
	Partial derivative ∂x/∂λ of coordinate (λ,ϕ).
double	dxDphi () const
	Partial derivative ∂x/∂ϕ of coordinate (λ,ϕ).
double	dyDlam () const
	Partial derivative ∂y/∂λ of coordinate (λ,ϕ).
double	dyDphi () const
	Partial derivative ∂y/∂ϕ of coordinate (λ,ϕ).
bool	isValid () const
	Returns true if the factors are valid, or false if they could not be calculated.
double	meridianConvergence () const
	Meridian convergence (in degrees) at coordinate (λ,ϕ). Sometimes also described as grid declination.
double	meridianParallelAngle () const
	Meridian/parallel angle (in degrees), θ′, at coordinate (λ,ϕ).
double	meridionalScale () const
	Meridional scale at coordinate (λ,ϕ).
double	parallelScale () const
	Parallel scale at coordinate (λ,ϕ).
double	tissotSemimajor () const
	Maximum scale factor.
double	tissotSemiminor () const
	Minimum scale factor.

Friends
class	QgsCoordinateReferenceSystem

Detailed Description

Contains various cartographic properties, such as scale factors, angular distortion and meridian convergence.

Since

QGIS 3.20

Definition at line 30 of file qgsprojectionfactors.h.

Member Function Documentation

angularDistortion()

double QgsProjectionFactors::angularDistortion ( ) const

inline

Angular distortion at coordinate (λ,ϕ).

Definition at line 49 of file qgsprojectionfactors.h.

arealScale()

double QgsProjectionFactors::arealScale ( ) const

inline

Areal scale factor at coordinate (λ,ϕ).

Definition at line 46 of file qgsprojectionfactors.h.

dxDlam()

double QgsProjectionFactors::dxDlam ( ) const

inline

Partial derivative ∂x/∂λ of coordinate (λ,ϕ).

Definition at line 64 of file qgsprojectionfactors.h.

dxDphi()

double QgsProjectionFactors::dxDphi ( ) const

inline

Partial derivative ∂x/∂ϕ of coordinate (λ,ϕ).

Definition at line 67 of file qgsprojectionfactors.h.

dyDlam()

double QgsProjectionFactors::dyDlam ( ) const

inline

Partial derivative ∂y/∂λ of coordinate (λ,ϕ).

Definition at line 70 of file qgsprojectionfactors.h.

dyDphi()

double QgsProjectionFactors::dyDphi ( ) const

inline

Partial derivative ∂y/∂ϕ of coordinate (λ,ϕ).

Definition at line 73 of file qgsprojectionfactors.h.

isValid()

bool QgsProjectionFactors::isValid ( ) const

inline

Returns true if the factors are valid, or false if they could not be calculated.

Definition at line 37 of file qgsprojectionfactors.h.

meridianConvergence()

double QgsProjectionFactors::meridianConvergence ( ) const

inline

Meridian convergence (in degrees) at coordinate (λ,ϕ). Sometimes also described as grid declination.

Definition at line 55 of file qgsprojectionfactors.h.

meridianParallelAngle()

double QgsProjectionFactors::meridianParallelAngle ( ) const

inline

Meridian/parallel angle (in degrees), θ′, at coordinate (λ,ϕ).

Definition at line 52 of file qgsprojectionfactors.h.

meridionalScale()

double QgsProjectionFactors::meridionalScale ( ) const

inline

Meridional scale at coordinate (λ,ϕ).

Definition at line 40 of file qgsprojectionfactors.h.

parallelScale()

double QgsProjectionFactors::parallelScale ( ) const

inline

Parallel scale at coordinate (λ,ϕ).

Definition at line 43 of file qgsprojectionfactors.h.

tissotSemimajor()

double QgsProjectionFactors::tissotSemimajor ( ) const

inline

Maximum scale factor.

Definition at line 58 of file qgsprojectionfactors.h.

tissotSemiminor()

double QgsProjectionFactors::tissotSemiminor ( ) const

inline

Minimum scale factor.

Definition at line 61 of file qgsprojectionfactors.h.

Friends And Related Symbol Documentation

QgsCoordinateReferenceSystem

friend class QgsCoordinateReferenceSystem

friend

Definition at line 107 of file qgsprojectionfactors.h.

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

• /build/qgis-3.99.0+git20250718+f78f5286a64+99sid/src/core/proj/qgsprojectionfactors.h