FFTs for the 2-Sphere-Improvements and Variations

摘要: Earlier work by Driscoll and Healy has produced an efficient algorithm for computing the Fourier transform of band-limited functions on 2-sphere. In this article we present a reformulation variation original which results in a greatly improved inverse transform, consequent convolution for such functions. All require at most O(N log2 N) operations where N is number sample points. We also address implementation considerations give heuristics allowing reliable computationally floating point implementations slightly modified algorithms. These claims are supported extensive numerical experiments from our implementation C DEC, HP, SGI Linux Pentium platforms. These results indicate that variations both large range of useful problem sizes. Performance appears to be architecture-dependent. The concludes with brief discussion few potential applications.