Class: QgsFieldCalculator

A dialog class that provides calculation of new fields using existing fields, values and a set of operators

Sample usage of the QgsFieldCalculator class:

uri = "point?crs=epsg:4326&field=id:integer"
layer = QgsVectorLayer(uri, "Scratch point layer",  "memory")
layer.startEditing()
dialog = QgsFieldCalculator(layer)
dialog.exec()

QgsFieldCalculator

Class Hierarchy

Base classes

QDialog
QWidget
QObject
QPaintDevice

Methods

changedAttributeId

Returns the field index of the field for which new attribute values were calculated.

class qgis.gui.QgsFieldCalculator

Bases: QDialog

changedAttributeId(self) → int

Returns the field index of the field for which new attribute values were calculated.

Return type:

int

Returns:

The field index if attribute values were calculated or -1, e.g. in case of geometry changes.