Class: QgsDerivativeFilter

class qgis.analysis.QgsDerivativeFilter

Bases: QgsNineCellFilter

Adds the ability to calculate derivatives in x- and y-directions. Needs to be subclassed (e.g. for slope and aspect).

Methods

calcFirstDerX

Calculates the first order derivative in x-direction according to Horn (1981)

calcFirstDerY

Calculates the first order derivative in y-direction according to Horn (1981)

processNineCellWindow

rtype

Tuple[float, float, float, float, float, float, float, float, float, float]

calcFirstDerX(self) → Tuple[float, float, float, float, float, float, float, float, float, float]

Calculates the first order derivative in x-direction according to Horn (1981)

Return type

Tuple[float, float, float, float, float, float, float, float, float, float]

calcFirstDerY(self) → Tuple[float, float, float, float, float, float, float, float, float, float]

Calculates the first order derivative in y-direction according to Horn (1981)

Return type

Tuple[float, float, float, float, float, float, float, float, float, float]

processNineCellWindow(self) → Tuple[float, float, float, float, float, float, float, float, float, float]
Return type

Tuple[float, float, float, float, float, float, float, float, float, float]