For vectors, the value to color conversion can be done on the basis of components or magnitude of vectors. This choice is done as folow, through JyConsole:
To set to components based conversion
cassandra.getPipeLineManager().getLookupTableList().getElementAt(0).getVtkObject().SetVectorModeToComponent()
and to choose the component of the vector used for the conversion
cassandra.getPipeLineManager().getLookupTableList().getElementAt(0).getVtkObject().SetVectorComponent(1)
To set to a magnitude based conversion
cassandra.getPipeLineManager().getLookupTableList().getElementAt(0).getVtkObject().SetVectorModeToMagnitude()
REMARK: In the current version of Cassandra, the min-max values of the color bar are set on the 1st component be default, and it is generally needed to update them manually.
Julien (Artenum)