Contents
Where are the parameters stored in qgsprocessingparameters class?
Parameters are stored in a QVariantMap and referenced by a unique string key. The QVariants in parameters are not usually accessed directly, and instead the high level API provided through QgsProcessingParameters parameterAsString (), parameterAsDouble () are used instead.
Is there a processing console in QGIS Python?
There is not a processing console in QGIS, but all processing commands are available instead from the QGIS built-in Python console. That means that you can incorporate those commands into your console work and connect processing algorithms to all the other features (including methods from the QGIS API) available from there.
Can a processing script extend a qgsprocessingalgorithm?
Processing scripts extend QgsProcessingAlgorithm, so you need to add some extra lines of code to implement mandatory functions.
When to use the default value in QGIS?
The default value is used if the corresponding parameter entry is missing. For output data objects, type the file path to be used to save it, just as it is done from the toolbox. If the output object is not specified, the result is saved to a temporary file (or skipped if it is an optional output).
When to use preferredformat argument in QGIS?
The function will then return the path to that temporary file. compatibleFormats should consist entirely of lowercase file extensions, e.g. ‘shp’. The preferredFormat argument is used to specify to desired file extension to use when a temporary layer export is required.
How is a feature sink evaluated in QGIS?
Evaluates the parameter with matching definition to a feature sink. The fields, geometryType and crs parameters dictate the properties of the resulting feature sink. Sinks will either be taken from context ’s active project, or created from external providers and stored temporarily in the context.
https://www.youtube.com/watch?v=M4hFxH1Dq_Q