Cubic splines are a common class of functions which are used in many interpolation applications. The basic idea is to fit cubic polynomials between two neighboring data points while ensuring that certain additional conditions are fulfilled (smooth first and second derivative). Furthermore, the concept of splines can be extended to approximations as well, if we introduce a small extension which results in smoothed splines. A smoothed spline degenerates to a simple linear regression if the smoothing factor approaches its maximum.

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After downloading please unpack all files of the zipped packages and start the executable.

The program Spline allows to experiment with various forms of splines. You may move the data points by dragging them with the mouse. For downloading the program click the floppy disk symbols at right.