Efficient approximations for the arctangent function using Lagrange interpolation and minimax optimization techniques are presented. These approximations are particularly useful when processing power, memory, and power consumption are important issues. In addition to comparing the errors and the computational workload for these approximations, extension to four quadrants are also outlined.

IEEE Signal Processing Magazine
Department of Systems and Computer Engineering

Rajan, S, Wang, S. (Sichun), Inkol, R. (Robert), & Joyal, A. (Alain). (2006). Efficient approximations for the arctangent function. IEEE Signal Processing Magazine, 23(3), 108–111. doi:10.1109/MSP.2006.1628884