Adaptive-Degree Polynomial Filter (Savitzky-Golay Filter)

function polynomial_degree=adpf(data_frame)

Adaptive-Degree Polynomial Filter (Savitzky-Golay Filter)

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 can be used to obtain 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).

Usage:
Run Pkmi_Calculate first to obtain the numerical table of gram polynomials so as to accelerate the calculation.

Examples:
%Examples:
adpf_demo %A demo of data smoothing with the adaptive-degree polynomial filter
Fig_1 %Obtain figure 1 of Ref. [1]
Fig_2 %Obtain figure 2 of Ref. [1]

Author:
Jianwen Luo <luojw@bme.tsinghua.edu.cn, luojw@ieee.org> 2004-10-26
Department of Biomedical Engineering, Department of Electrical Engineering
Tsinghua University, Beijing 100084, P. R. China

References:
[1] P. Barak,
"Smoothing and differentiation by an adaptive-degree polynomial filter," Analytical Chemistry, vol. 67, pp. 2758-2762, 1995.
[2] M. Jakubowska and W. W. Kubiak,
"Adaptive-degree polynomial filter for voltammetric signals," Analytica Chimica Acta, vol. 512, pp. 241-250, 2004.
[3] A. Savitzky and M. J. E. Golay,
"Smoothing and Differentiation of Data by Simplified Least Squares Procedures," Analytical Chemistry, vol. 36, pp. 1627-1639, 1964.
[4]P. A. Gorry,
"General Least-Squares Smoothing and Differentiation by the Convolution (Savitzky-Golay) Method," Analytical Chemistry, vol. 62, pp. 570-573, 1990.
[5] J. W. Luo, K. Ying, P. He and J. Bai,
¡°Properties of Savitzky-Golay digital differentiators,¡±
Digital Signal Processing, in press
[6] http://www.mathworks.com/matlabcentral/fileexchange/loadFileList.do?objectType=search&criteria=savitzky+or+sgolayfilt&Search=Go
[7] http://uk.cambridge.org/chemistry/resources/delevie/