Class: QgsProjectionFactors

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

Added in version 3.20.

class qgis.core.QgsProjectionFactors[source]

Bases: object

angularDistortion(self) → float[source]

Angular distortion at coordinate (λ,ϕ).

Return type:

float

arealScale(self) → float[source]

Areal scale factor at coordinate (λ,ϕ).

Return type:

float

dxDlam(self) → float[source]

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

Return type:

float

dxDphi(self) → float[source]

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

Return type:

float

dyDlam(self) → float[source]

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

Return type:

float

dyDphi(self) → float[source]

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

Return type:

float

isValid(self) → bool[source]

Returns True if the factors are valid, or False if they could not be calculated.

Return type:

bool

meridianConvergence(self) → float[source]

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

Return type:

float

meridianParallelAngle(self) → float[source]

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

Return type:

float

meridionalScale(self) → float[source]

Meridional scale at coordinate (λ,ϕ).

Return type:

float

parallelScale(self) → float[source]

Parallel scale at coordinate (λ,ϕ).

Return type:

float

tissotSemimajor(self) → float[source]

Maximum scale factor.

Return type:

float

tissotSemiminor(self) → float[source]

Minimum scale factor.

Return type:

float