Dear all,

I think for many user of wolfram this question is easy, but I am starting to get used to the program and all its features and for that I think it is the best way to learn from the people who use mathematica every day for a long time.

Problem: I have 10 arbitrarily points which are in one plane. First of all I would like to make a closed spline through all of these 10 points and would like to express the curve in polar coordinates. (The curve will approximatly look like an egg.)

I think I can visualise this by using the: << Splines`; Graphics[Spline[{{...,...}, {...,...}, {...,...}, {...,...}}, Bezier]]

But this only helps me to visualise the curve. To get the length of the spline I would like to get an approximated function to all these points and want to calculated the derivative of the function.

My question: How can I get an approximated curve through all of my 10 points with an polar expression? Should I use "InterpolatingFunction", "BSplineFunction" or "InterpolatingPolynomial"? What are the advantages of these differet Functions and which of these will help to get me the polar function -> length of my spline?

I would be glade to get some ideas to get the problem solved.

Thank you very much!

Best regards. Alex