cannam@127: cannam@127: cannam@127: cannam@127: cannam@127:
cannam@127:cannam@127: Previous: Wisdom, Up: FFTW Reference [Contents][Index]
cannam@127:In this section, we provide precise mathematical definitions for the cannam@127: transforms that FFTW computes. These transform definitions are fairly cannam@127: standard, but some authors follow slightly different conventions for the cannam@127: normalization of the transform (the constant factor in front) and the cannam@127: sign of the complex exponent. We begin by presenting the cannam@127: one-dimensional (1d) transform definitions, and then give the cannam@127: straightforward extension to multi-dimensional transforms. cannam@127:
cannam@127:• The 1d Discrete Fourier Transform (DFT): | cannam@127: | |
• The 1d Real-data DFT: | cannam@127: | |
• 1d Real-even DFTs (DCTs): | cannam@127: | |
• 1d Real-odd DFTs (DSTs): | cannam@127: | |
• 1d Discrete Hartley Transforms (DHTs): | cannam@127: | |
• Multi-dimensional Transforms: | cannam@127: |