Titanium test data
[x,y] = titanium
[x,y] = titanium returns measurements of a certain
property of titanium as a function of temperature. Since their use in , these data
have become a standard test for data fitting since they are hard to fit by classical
techniques and have a significant amount of noise.
The plot of the data shown below is generated by the following commands:
[x,y] = titanium; plot(x,y,'ok'), set(gca,'Fontsize',16)
 C. de Boor and J. R. Rice. "Least squares cubic spline approximation II - Variable knots." CSD TR 21, Comp.Sci., Purdue Univ., April 1968.