Fitting a linear sine curve with natural spline

I am relatively new to Matlab. The threads that I searched regarding the topic is in vain. Through core Matlab functions, kindly assist in fitting a linear sine curve(s(x)=sinx) between o and 2*pi with a natural and cubic spline. In terms of the natural spline, we can use condition: second derivatives at the two ends of the spline are set to zero. For cubic spline, we can use condition: Tangent direction of the cosine curve at the two endpoints to be the starting and ending tangent vectors.

[Torsten]

The splines you mention (cubic or natural spline) are not fitting, but interpolation objects.

I guess you mean approximating splines:

https://de.mathworks.com/help/curvefit/spap2.html

Best wishes

Torsten.

[Abi sek]

Hi Torsten, It does directly call the function spap directly.But, I need to have a detailed breakdown code which mainly encompasses the double derivatives at the two endpoints are zero in case of the natural spline.

Regards, Abhi

[Torsten]

So you search for an approximating spline for which you worry about the end conditions ? That's unusual. I guess that you will have to write your own code to implement such a speciality.

Best wishes

Torsten.