Patent US 4,031,370

A method of interpolating a value of the dependent variable, y corresponding to a given value of an independent variable x, wherein y = f(x) and is described by a linear polynomial series of the 8'th order. The method uses a 4'th order polynomial interpolation method to obtain up to an 8'th order interpolation in 2 iterations of the 4'th order method. The method is suitable for implementation by a computer or by purpose-designed data processing apparatus. An embodiment of apparatus suitable for use in performing the method is also disclosed.