MATLAB: Fitting Functions

curve fittingfitting

I have a Vector of Data. and i want to do a fitting to the Vector. but I want the fit to be in the shape of:

A/x+B/x^2+C/x^3…

is there any Known function I am missing?or do i need to write my own code. if so anyone is familiar with a good way to do that?

If you have the Statistics Toolbox, you can use the function nlinfit() to do that.