Class: QgsProjectionFactors¶
- class qgis.core.QgsProjectionFactors¶
Bases:
sip.wrapper
contains various cartographic properties, such as scale factors, angular distortion and meridian convergence.
New in version 3.20:
Methods
Angular distortion at coordinate (λ,ϕ).
Areal scale factor at coordinate (λ,ϕ).
Partial derivative ∂x/∂λ of coordinate (λ,ϕ).
Partial derivative ∂x/∂ϕ of coordinate (λ,ϕ).
Partial derivative ∂y/∂λ of coordinate (λ,ϕ).
Partial derivative ∂y/∂ϕ of coordinate (λ,ϕ).
Returns
True
if the factors are valid, orFalse
if they could not be calculated.Meridian convergence (in degrees) at coordinate (λ,ϕ).
Meridian/parallel angle (in degrees), θ′, at coordinate (λ,ϕ).
Meridional scale at coordinate (λ,ϕ).
Parallel scale at coordinate (λ,ϕ).
Maximum scale factor.
Minimum scale factor.
- angularDistortion(self) float ¶
Angular distortion at coordinate (λ,ϕ).
- Return type
float
- arealScale(self) float ¶
Areal scale factor at coordinate (λ,ϕ).
- Return type
float
- dxDlam(self) float ¶
Partial derivative ∂x/∂λ of coordinate (λ,ϕ).
- Return type
float
- dxDphi(self) float ¶
Partial derivative ∂x/∂ϕ of coordinate (λ,ϕ).
- Return type
float
- dyDlam(self) float ¶
Partial derivative ∂y/∂λ of coordinate (λ,ϕ).
- Return type
float
- dyDphi(self) float ¶
Partial derivative ∂y/∂ϕ of coordinate (λ,ϕ).
- Return type
float
- isValid(self) bool ¶
Returns
True
if the factors are valid, orFalse
if they could not be calculated.- Return type
bool
- meridianConvergence(self) float ¶
Meridian convergence (in degrees) at coordinate (λ,ϕ). Sometimes also described as grid declination.
- Return type
float
- meridianParallelAngle(self) float ¶
Meridian/parallel angle (in degrees), θ′, at coordinate (λ,ϕ).
- Return type
float
- meridionalScale(self) float ¶
Meridional scale at coordinate (λ,ϕ).
- Return type
float
- parallelScale(self) float ¶
Parallel scale at coordinate (λ,ϕ).
- Return type
float
- tissotSemimajor(self) float ¶
Maximum scale factor.
- Return type
float
- tissotSemiminor(self) float ¶
Minimum scale factor.
- Return type
float