SPLINE(VI) 10/20/73 SPLINE(VI) NAME spline - interpolate smooth curve SYNOPSIS spline [ option ] ... DESCRIPTION Spline takes pairs of numbers from the standard input as abcissas and ordinates of a function. It produces a similar set, which is approximately equally spaced and includes the input set, on the standard output. The cubic spline output (R. W. Hamming, Numerical Methods for Engineers and Scientists, 2nd ed., 349ff) has two continuous derivatives, and sufficiently many points to look smooth when plotted, for example by plot (I). The following options are recognized, each as a separate argument. a Supply abscissas automatically (they are missing from the input); spacing is given by the next argument, or is assumed to be 1 if next argument is not a number. n Output approximately n points, where n is given by the next argument. (Default n = 100.) p Make output periodic, i.e. match derivatives at ends. First and last input values should normally agree. x Next 1 (or 2) arguments are lower (and upper) x limits. SEE ALSO plot(I) AUTHOR M. D. McIlroy BUGS A limit of 1000 input points is enforced silently.