✦ LIBER ✦
Rotating a three-dimensional array in an optimal position for vector processing: case study for a three-dimensional fast Fourier transform
✍ Scribed by S. Goedecker
- Publisher
- Elsevier Science
- Year
- 1993
- Tongue
- English
- Weight
- 399 KB
- Volume
- 76
- Category
- Article
- ISSN
- 0010-4655
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✦ Synopsis
We show, that a three-dimensional array of dimension n 1. n,, 113 can he rotated in such a way, that all the innermost loops have lengths, which are products of two dimensions, i.e. n1n,, n1n3, n,n3. This technique is then applied to rotate a parallelepiped of data in an optimal position for Fourier transformations along the three axes. The resulting three-dimensional FFT (fast Fourier transform) has then only inner loops of length n1n2. n1n3, n,n1. This increased loop length results in a significant reduction of the required CPU time on vector machines.