FreeMat: vtkTupleInterpolator

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vtkTupleInterpolator

Section: Visualization Toolkit Rendering Classes

# Usage

This class is used to interpolate a tuple which may have an arbitrary number of components (but at least one component). The interpolation may be linear in form, or via a subclasses of vtkSpline.

To use this class, begin by specifying the number of components of the tuple and the interpolation function to use. Then specify at least one pair of (t,tuple) with the AddTuple() method. Next interpolate the tuples with the InterpolateTuple(t,tuple) method, where "t" must be in the range of (t_min,t_max) parameter values specified by the AddTuple() method (if not then t is clamped), and tuple[] is filled in by the method (make sure that tuple [] is long enough to hold the interpolated data).

You can control the type of interpolation to use. By default, the interpolation is based on a Kochanek spline. However, other types of splines can be specified. You can also set the interpolation method to linear, in which case the specified spline has no effect on the interpolation.

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

      obj = vtkTupleInterpolator

# Methods

The class vtkTupleInterpolator 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 vtkTupleInterpolator class.

- `string = obj.GetClassName ()`
- `int = obj.IsA (string name)`
- `vtkTupleInterpolator = obj.NewInstance ()`
- `vtkTupleInterpolator = obj.SafeDownCast (vtkObject o)`
- `obj.SetNumberOfComponents (int numComp)` - Specify the number of tuple components to interpolate. Note that setting this value discards any previously inserted data.
- `int = obj.GetNumberOfComponents ()` - Specify the number of tuple components to interpolate. Note that setting this value discards any previously inserted data.
- `int = obj.GetNumberOfTuples ()` - Return the number of tuples in the list of tuples to be interpolated.
- `double = obj.GetMinimumT ()` - Obtain some information about the interpolation range. The numbers returned (corresponding to parameter t, usually thought of as time) are undefined if the list of transforms is empty. This is a convenience method for interpolation.
- `double = obj.GetMaximumT ()` - Obtain some information about the interpolation range. The numbers returned (corresponding to parameter t, usually thought of as time) are undefined if the list of transforms is empty. This is a convenience method for interpolation.
- `obj.Initialize ()` - Reset the class so that it contains no (t,tuple) information.
- `obj.AddTuple (double t, double tuple[])` - Add another tuple to the list of tuples to be interpolated. Note that using the same time t value more than once replaces the previous tuple value at t. At least two tuples must be added to define an interpolation function.
- `obj.RemoveTuple (double t)` - Delete the tuple at a particular parameter t. If there is no tuple defined at t, then the method does nothing.
- `obj.InterpolateTuple (double t, double tuple[])` - Interpolate the list of tuples and determine a new tuple (i.e., fill in the tuple provided). If t is outside the range of (min,max) values, then t is clamped. Note that each component of tuple[] is interpolated independently.
- `obj.SetInterpolationType (int type)` - Specify which type of function to use for interpolation. By default spline interpolation (SetInterpolationFunctionToSpline()) is used (i.e., a Kochanek spline) and the InterpolatingSpline instance variable is used to birth the actual interpolation splines via a combination of NewInstance() and DeepCopy(). You may also choose to use linear interpolation by invoking SetInterpolationFunctionToLinear(). Note that changing the type of interpolation causes previously inserted data to be discarded.
- `int = obj.GetInterpolationType ()` - Specify which type of function to use for interpolation. By default spline interpolation (SetInterpolationFunctionToSpline()) is used (i.e., a Kochanek spline) and the InterpolatingSpline instance variable is used to birth the actual interpolation splines via a combination of NewInstance() and DeepCopy(). You may also choose to use linear interpolation by invoking SetInterpolationFunctionToLinear(). Note that changing the type of interpolation causes previously inserted data to be discarded.
- `obj.SetInterpolationTypeToLinear ()` - Specify which type of function to use for interpolation. By default spline interpolation (SetInterpolationFunctionToSpline()) is used (i.e., a Kochanek spline) and the InterpolatingSpline instance variable is used to birth the actual interpolation splines via a combination of NewInstance() and DeepCopy(). You may also choose to use linear interpolation by invoking SetInterpolationFunctionToLinear(). Note that changing the type of interpolation causes previously inserted data to be discarded.
- `obj.SetInterpolationTypeToSpline ()` - If the InterpolationType is set to spline, then this method applies. By default Kochanek interpolation is used, but you can specify any instance of vtkSpline to use. Note that the actual interpolating splines are created by invoking NewInstance() followed by DeepCopy() on the interpolating spline specified here, for each tuple component to interpolate.
- `obj.SetInterpolatingSpline (vtkSpline )` - If the InterpolationType is set to spline, then this method applies. By default Kochanek interpolation is used, but you can specify any instance of vtkSpline to use. Note that the actual interpolating splines are created by invoking NewInstance() followed by DeepCopy() on the interpolating spline specified here, for each tuple component to interpolate.
- `vtkSpline = obj.GetInterpolatingSpline ()` - If the InterpolationType is set to spline, then this method applies. By default Kochanek interpolation is used, but you can specify any instance of vtkSpline to use. Note that the actual interpolating splines are created by invoking NewInstance() followed by DeepCopy() on the interpolating spline specified here, for each tuple component to interpolate.