Cubic spline interpolation in SAS - The DO Loop

I recently showed how to use linear interpolation in SAS. Linear interpolation is a common way to interpolate between a set of planar points, but the interpolating function (the interpolant) is not smooth. If you want a smoother interpolant, you can use cubic spline interpolation. This article describes how to

Spline (mathematics) - Wikipedia

Three ways to add a smoothing spline to a scatter plot in SAS - The DO Loop

SAS Help Center: Using Splines and Knots

SAS Help Center: SPLINE and SPLINEC Calls

SAS Help Center: Using Splines and Knots

SAS/GRAPH Statements : SYMBOL Statement

Cubic spline interpolation in SAS - The DO Loop

SAS Help Center: Syntax: PROC SGPANEL SPLINE Statement

Creating a periodic smoother - The DO Loop