Thread Subject: plot a shape-preserving interpolant to XY

Dear all,

I wish to fit and plot a shape-preserving interpolant line to my XY data points, and only display the fit on the plot - not the XY data.

This is possible by first plotting the data and using a white maker, followed by basic fitting from the Tools menu. But what I am really after is a way of automating this step by building such a procedure into my own m-files.

Generating an m-file from my figure results in an error messages that makes no sense to me: "pvpmod needs either a structure of a cell array with parameter/value pairs"

I also tried to follow the help file on the use pchip, but this generated completely different results to what the GUI approach yielded.

How exactly does one manually reproduce this shape-preserving interpolant that can be obtained from Tools --> Basic fitting?