(M,p,k)-friendly points: a table-based method for trigonometric function evaluation

Nicolas Brisebarre (1, 2) , Milos Ercegovac (3) , Jean-Michel Muller (2, 1)

1 ARIC - Arithmetic and Computing
2 LIP - Laboratoire de l'Informatique du Parallélisme
3 Digital Arithmetic and Reconfigurable Architecture Laboratory

We present a new way of approximating the sine and cosine functions by a few table look-ups and additions. It consists in first reducing the input range to a very small interval by using rotations with "(M, p, k) friendly angles", proposed in this work, and then by using a bipartite table method in a small interval. An implementation of the method for 24- bit case is described and compared with CORDIC. Roughly, the proposed scheme offers a speedup of 2 compared with an unfolded double-rotation radix-2 CORDIC.

Keywords: computer arithmetic; elementary function evaluation

Domains: Computer Science [cs]; Other [cs.OH]

Nicolas Brisebarre, Milos Ercegovac, Jean-Michel Muller. (M,p,k)-friendly points: a table-based method for trigonometric function evaluation. 2012 IEEE 23rd International Conference on Application-Specific Systems, Architectures and Processors, Jul 2012, Delft, Netherlands. p. 46-52, ISBN: 978-1-4673-2243-0, ⟨10.1109/ASAP.2012.17⟩. ⟨ensl-00759912⟩