The use of sparse data in hybrid computer simula tion has been provided with a formal procedure for generating smooth approximation functions with excellent reproduction quality. The method is use ful with data records over the independent variable or where a variable diode function generator might be used. The method depends on the theory of spline functions, which provides the specified quality of "smoothness" of the reconstructed function. An analog polynomial circuit receives parameters sequentially from the digital to generate the function. Besides illustrating an efficient method for hybrid function generation, the subject of spline approximation has been introduced to simulators in a simple language.
