I create a selection with
getFeatures(QgsFeatureRequest()) and I want to calculate the length of the result which is a
select = QgsExpression(" myexpression ") selectedfeats = layer.getFeatures(QgsFeatureRequest(select )) total = 0 for feature in selectedfeats : geom = feature.geometry() total += geom.length()
But it doesn't work it returns 0 whereas the
selectedfeats is not empty.