I have used spline from curve fit toolbox, I need help using my fit struct.

Hi, After I used spline in curve fit toolbox, I have this struct called "fit". It has information about polynomials, one of them is my "coefs" which has 4 rows. My number of knots are 335, so I have 335*4 coefs. I do not fully understand why there are 4 rows. I am reading lots of materials for spline interpolation but it is still confusing. I need to make f(x) based on my coefficients, and use the f(x) as fit function for my genetic algorithm to optimize (ideally make f(x)=0), ideally using "ga" function in Matlab. Does any one have any idea how to do it. I appreciate any help and tips.

[dpb]

Many ways you could have done; specifics depend on those details. Show us the code you used...attaching the data so someone can replicate would probably be most beneficial.

Answer 1

[S.M.]

Thank you for your response. I plotted the rows on Friday, I did it individually and I think I figured out why it comes with four row, and if I am not mistaking it represents the degree of spline.