Binary package “spline” in ubuntu bionic

Akima spline interpolation

 aspline(1) interpolates an Akima-spline through a series of given points.
 The Akima-spline interpolation approximates a manually drawn curve better
 than the ordinary splines, but the second derivative is not continuous.
 .
 The Akima-spline algorithm is described in "A New Method of Interpolation and
 Smooth Curve Fitting Based on Local Procedures", H. Akima, J. Assoc. Comput.
 Mach., 17(4), 1970, pp. 589-602. doi:10.1145/321607.321609