In order to analyze the fitting error and convergence of the mathematical model and the convergence rate of the progressive iterative approximation method (PIA), we gave the formula of the bound of the fitting. By using the L2-matrix norm, the iterative collocation matrix formula of the PIA method and the classic QR matrix diagonalization method, we gave the formula for estimating the number of the iteration required by the PIA method in advance. Research showed that the fitting error of the PIA method is closely related to the rounding error of the calculation and the spectral radius of the collocation matrix and the initial parameterization of the given data points. Under the condition of the given different fitting precision and different initial parameterization of the given data points, using the estimation formula of the fitting error, the iterative number can be calculated and the fitting effect can be improved．
DENG Shao-hui,WANG Guo-zhao. Error estimation and application of a new class of graphics fitting method. JOURNAL OF ZHEJIANG UNIVERSITY (ENGINEERING SCIENCE), 2014, 48(5): 942-947.
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