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vtkSelectionAlgorithm

Section: Visualization Toolkit Filtering Classes

# Usage

vtkSelectionAlgorithm is a convenience class to make writing algorithms easier. It is also designed to help transition old algorithms to the new pipeline edgehitecture. There are some assumptions and defaults made by this class you should be aware of. This class defaults such that your filter will have one input port and one output port. If that is not the case simply change it with SetNumberOfInputPorts etc. See this class constructor for the default. This class also provides a FillInputPortInfo method that by default says that all inputs will be Selection. If that isn't the case then please override this method in your subclass. This class breaks out the downstream requests into separate functions such as ExecuteData and ExecuteInformation. For new algorithms you should implement RequestData( request, inputVec, outputVec) but for older filters there is a default implementation that calls the old ExecuteData(output) signature. For even older filters that don't implement ExecuteData the default implementation calls the even older Execute() signature.

.SECTION Thanks Thanks to Patricia Crossno, Ken Moreland, Andrew Wilson and Brian Wylie from Sandia National Laboratories for their help in developing this class.

To create an instance of class vtkSelectionAlgorithm, simply invoke its constructor as follows

      obj = vtkSelectionAlgorithm

# Methods

The class vtkSelectionAlgorithm has several methods that can be used. They are listed below. Note that the documentation is translated automatically from the VTK sources, and may not be completely intelligible. When in doubt, consult the VTK website. In the methods listed below, `obj` is an instance of the vtkSelectionAlgorithm class.

- `string = obj.GetClassName ()`
- `int = obj.IsA (string name)`
- `vtkSelectionAlgorithm = obj.NewInstance ()`
- `vtkSelectionAlgorithm = obj.SafeDownCast (vtkObject o)`
- `vtkSelection = obj.GetOutput ()` - Get the output data object for a port on this algorithm.
- `vtkSelection = obj.GetOutput (int index)` - Get the output data object for a port on this algorithm.
- `obj.SetInput (vtkDataObject obj)` - Set an input of this algorithm. You should not override these methods because they are not the only way to connect a pipeline. Note that these methods support old-style pipeline connections. When writing new code you should use the more general vtkAlgorithm::SetInputConnection(). These methods transform the input index to the input port index, not an index of a connection within a single port.
- `obj.SetInput (int index, vtkDataObject obj)` - Set an input of this algorithm. You should not override these methods because they are not the only way to connect a pipeline. Note that these methods support old-style pipeline connections. When writing new code you should use the more general vtkAlgorithm::SetInputConnection(). These methods transform the input index to the input port index, not an index of a connection within a single port.