Commonly, the degree of the fitting polynomial for the Savitzky-Golay filter is fixed. However, the polynomial degree can vary according to the sum of squares of fitting residuals and the statistical testing to obtain the adaptive-degree polynomial filter.
This function obtains the polynomial degree (output: polynomial_degree) selected in the adaptive-degree polynomial filter (Savitzky-Golay filter)for the data subset of length 2M+1 (intput: data_frame).
The difference between this function and our previvous one (http://www.mathworks.com/matlabcentral/fileexchange/loadFile.do?objectId=6121&objectType=file) lies in that this one is for data differentiation (first derivative) and that is for data smoothing.
Run Pkmi_Calculate first to obtain the numerical table of gram polynomials so as to accelerate the calculation. And See the demo of above-mentionded function of data smoothing for reference.
Jianwen Luo <firstname.lastname@example.org, email@example.com> 2005-02-27
Department of Biomedical Engineering
Tsinghua University, Beijing 100084, P. R. China
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