The Study On Some Problems In The Data Fitting

This dissertation focuses on two subproblems about data fitting.On account that classical progressive iterative approximation(PIA)shows a quite slow speed and geometrical meaning for conjugate gradient in PIA is uncertain and indistinct,one of questions is how to improve the two methods on basis of them;The other problem is about the accuracy of circle fitting for a small arc sampling,on which some traditional methods embody notable deviation and can't satisfy production requirements.Therefore,it is supposed and urgent to come up with a different idea accordingly.In these circumstances,the paper creates a new energy function with parameters,which defines the mechanism of adjusting parameters and sets their value by given data sampling,so as to reduce the error of the circle fitting and meet the need of the industrial precision.