A functional approach to radix- r FFTS
Dorothy Bollman, Jaime Seguel, John Feo · Scalable Computing Practice and Experience · 2001
We show that each member of a well-known family of radix-r FFTs can be expressed as the composition of functions chosen from a set of four functions. Thus, a complete library of radix-r FFTs can be developed by programming the four basis functions and composing them to obtain various FFTs. We illustrate this by developing implementations in the functional language Sisal. We compare performance of these FFTs on a Cray C-90. Based on observations of these results we develop an implementation of an FFT of size 2k which is seemingly optimal for the Cray C-90. We discuss language features of particular benefit for programming FFTs and suggest some enhancements that would further streamline the programming.