vtkFieldData

Section: Visualization Toolkit Filtering Classes

Usage

vtkFieldData represents and manipulates fields of data. The model of a field is a m x n matrix of data values, where m is the number of tuples, and n is the number of components. (A tuple is a row of n components in the matrix.) The field is assumed to be composed of a set of one or more data arrays, where the data in the arrays are of different types (e.g., int, double, char, etc.), and there may be variable numbers of components in each array. Note that each data array is assumed to be "m" in length (i.e., number of tuples), which typically corresponds to the number of points or cells in a dataset. Also, each data array must have a character-string name. (This is used to manipulate data.)

There are two ways of manipulating and interfacing to fields. You can do it generically by manipulating components/tuples via a double-type data exchange, or you can do it by grabbing the arrays and manipulating them directly. The former is simpler but performs type conversion, which is bad if your data has non-castable types like (void) pointers, or you lose information as a result of the cast. The, more efficient method means managing each array in the field. Using this method you can create faster, more efficient algorithms that do not lose information.

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

  obj = vtkFieldData

Methods

The class vtkFieldData 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 vtkFieldData class.