Cubic spline interpolation with second derivative at ends as zero

Hi all,

I need a function for cubic spline interpolation where second derivative at both the ends are zero (i.e. Natural or Free spline). My version of MATLAB does not allow to use "csape".

If not a function, atleast suggest some method to work around the above problem.

Please help!

Thanks, Anirban

Answer 1

[Mahdi]

Doesn't the spline function work?

[Anirban Naskar]

Hi,

Is there any technique by which I can use the spline function, giving additional boundary conditions that second derivative in the end as zero?

[Mahdi]

My knowledge of splines isn't that good, but doesn't cubic splines already consider that the second derivative at the end is zero? So you can use spline(x,y,xx, 'cubic')?