Digital Savitzky—Golay filter

Bromba, M. U. A., and Ziegler, H., Application Hints for Savitzky-Golay Digital Smoothing Filters, Anal. Chem. 53, 1981, 1583-1586. 

The most common digital filtering polynomial methods, according to Savitzky and Golay [22, 23], involve a shortened least-square computation using a sliding window with variable data points but other algorithms are also sometimes practicable. 

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