1

I have a "for" loop included on a "while" loop, and it work when I save the for loop result in a shapefile and I reuse it on the loop like that :

    #last step of the "for" loop
    alg_params = {
       'CRS': None,
       'LAYERS': [regroupee, outputs['CalculatriceDeChamp']['OUTPUT']],
       'OUTPUT': 'I:/moulin_z/DONNEES/temp_us235/test_iteration_pyqgis/sorties/regroupee_' + str(num_boucle) + str(feature_id) + '.shp'
    }

    merge = processing.run('native:mergevectorlayers', alg_params, context=context, is_child_algorithm=True)
    regroupee = QgsVectorLayer(merge['OUTPUT'], "Regroupee","ogr")

# after the "for" loop
alg_params = {
   'EXPRESSION': '\"affectatio\" = \'Non bati\'',
   'INPUT': regroupee,
   'OUTPUT': QgsProcessing.TEMPORARY_OUTPUT
}
outputs['ExtractionNonbati'] = processing.run('native:extractbyexpression', alg_params, context=context, feedback=feedback, is_child_algorithm=True)

But when I try to save result layer as temporary output, it work on the loop, but not on the "extract by expression" processing after the "for" loop... :

    #last step of the "for" loop
    alg_params = {
       'CRS': None,
       'LAYERS': [regroupee, outputs['CalculatriceDeChamp']['OUTPUT']],
       'OUTPUT': QgsProcessing.TEMPORARY_OUTPUT
    }

    outputs['Fusionner'] = processing.run('native:mergevectorlayers', alg_params, context=context, is_child_algorithm=True)
    regroupee = QgsVectorLayer(outputs['Fusionner']['OUTPUT'], "Regroupee","ogr")

# after the "for" loop
alg_params = {
   'EXPRESSION': '\"affectatio\" = \'Non bati\'',
   'INPUT': regroupee,
   'OUTPUT': QgsProcessing.TEMPORARY_OUTPUT
}
outputs['ExtractionNonbati'] = processing.run('native:extractbyexpression', alg_params, context=context, feedback=feedback, is_child_algorithm=True)

Error message explain :

Impossible de créer la couche en mémoire. (Impossible to create the memory layer)
Traceback (most recent call last):
File "<string>", line 267, in processAlgorithm
File "C:/PROGRA~1/QGIS3~1.6/apps/qgis/./python/plugins\processing\tools\general.py", line 117, in run
return Processing.runAlgorithm(algOrName, parameters, onFinish=post_process, feedback=feedback, context=context)
File "C:/PROGRA~1/QGIS3~1.6/apps/qgis/./python/plugins\processing\core\Processing.py", line 182, in runAlgorithm
feedback.reportError(msg)
TypeError: reportError(self, error: str, fatalError: bool): not enough arguments

It would be very great if my code could work with temporary output, because it's really faster.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Browse other questions tagged or ask your own question.