Lagrange Differentiator

The digital differentiator from the Lagrange interpolation.
It is equivalent to the maximally flat low-pass digital differentiator,
or the degenerated form of Savitzky-Golay digital differentiator.

Author:
Jianwen Luo <luojw@ieee.org> 2006-06-17
Department of Biomedical Engineering,
Tsinghua University, Beijing 100084, P. R. China

References:
[1] Carlsson B.
Maximum Flat Digital Differentiator,
Electron. Lett. 1991, 27(8): 675-677.
[2] Kumar B, Roy S C D.
Coefficients of Maximally Linear, Fir Digital Differentiators for Low-Frequencies,
Electron. Lett. 1988, 24(9): 563-565.
[3] Selesnick I W.
Maximally flat low-pass digital differentiators,
IEEE Trans. Circuits Syst. II-Analog Digit. Signal Process. 2002, 49(3): 219-223.
[4] Khan I R, Okuda M, Ohba R.
Design of FIR digital differentiators using maximal linearity constraints,
IEICE Trans. Fundam. Electron. Commun. Comput. Sci. 2004, E87A(8): 2010-2017.
[5] Luo J W, Ying K, He P, Bai J.
Properties of Savitzky-Golay digital differentiators,
Digit. Signal Prog. 2005, 15(2): 122-136.
[6] Luo J W, Ying K, Bai J.
Savitzky-Golay smoothing and differentiation filter for even number da,
Signal Process. 2005, 85(7): 1429-1434