NAME
aspline - Akima spline interpolation
SYNOPSIS
aspline [-a xstep] [-l llim] [-u ulim] [-n n] {file(s)}
DESCRIPTION
aspline reads pairs of numbers from the indicated file(s) (or from
stdin if no files were given) as abscissas and ordinates of a function.
It produces a similar set, which is approximately equally spaced and
includes the input set on standard output. The output is an Akima-
interpolated spline which has an continuous first derivative. The
second derivate may be discontinuous, but the output does not wiggle as
it would do with cubic splines.
Datasets are separated by blank lines.
OPTIONS
-a incr, --auto=incr
supply abscissas automatically, since 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.
-l llim, --llimit=llim
set lower x-limit to llim,
-u ulim, --ulimit=ulim
set upper x-limit to ulim,
-n n, --points=n
space output points so that approx. n intervals occur between
the lower and upper limit,
-v be verbose,
-h print help message on stderr and exit.
SEE ALSO
spline(1), gnuplot(1).
H. Akima, A New Method of Interpolation and Smooth Curve Fitting Based
on Local Procedures, Journal of Assc. for Comp. Mach., Vol. 17, No. 4,
Oct. 1970, pp. 589602
BUGS
If you need a continuous second derivative, use spline from the
plotutils package instead.