[vtkusers] Problem with vtkTable and vtkVariantArray

[Jeff Baumes]

On Tue, Mar 31, 2009 at 5:08 AM, Roger Blum <rogerblum at hawaii.rr.com> wrote:
> My questions:
> - Is there an easier way to extract the data from the vtkRowQuery
>  object?

Your way is the easy way to do it in C++, but it is not currently
available in wrapped languages. The problem is vtkVariant, which is a
lightweight, stack-based object that does not subclass from vtkObject.
No methods that take or return a variant are wrapped.

> - Why is method GetValue with 2 params invalid when the online doc
>  tells me this method exists? Maybe a wrapping problem?

Yes, it is a wrapping issue.

> - How else can I read the values of vtkTable and/or vtkVarianArray

vtkTable's data is internally stored as a collection of arrays that
are uniformly-typed, just like attributes of other data objects in
VTK. You can access the columns through table->GetColumn(i) or
table->GetColumnByName(name), which are wrapped. The column array
types should match the types in the database. vtkVariantArray is
currently essentially unaccessable through wrappers, since you cannot
set or retrieve values.

> - Are there any examples available for the newer Vtk classes?

Some of the newer data objects (table, graph, tree) were made
primarily for the infovis effort in VTK. See Examples/Infovis and the
tests in Infovis/Testing/Cxx and Views/Testing/Cxx. Some rudimentary
documentation is available for Titan (i.e. infovis in VTK) at
http://www.sandia.gov/Titan and http://www.kitware.com/InfovisWiki.
There are plenty of other new classes; search for tests or examples
that use them in the VTK repository.

Jeff