Hacking a workflow

The orange-canvas allows users to add Python script to a workflow

And with it users can add some processing to it and ultimately bring some flexibility to it.

For example here we simply get the in data, print his identifier and define it as out data

Usually the input parameter will be data (map to in_data) or a volume (map to in_volume)

A list of example script are available from the python script documentation page

When the python object has several link connected to the same input like `data` we will move from `in_data` to `in_datas`. This can be disconcerting. Usually a recommanded practice is to limit link to an input to one.

The python script will be executed in the main Qt thread. As a consequence during it execution the GUI will not be responsive. So if your processing is heavy you might experience some gui freezing.

Exercice A: modify the 'data' energy and resume processing

Exercise B: print the shape of a reconstructed slice

Help:

• reconstructed slices identifiers can be obtain from latest_reconstructions property. It returns a list of identifiers (url of the volumes)
• you can convert volume identifiers to volume object by using the VolumeFactory.create_tomo_object_from_identifier
• from the volume object you can load the data by calling volume.load_data(). It returns a numpy array