In this section, we provide precise mathematical definitions for the Chris@19: transforms that FFTW computes. These transform definitions are fairly Chris@19: standard, but some authors follow slightly different conventions for the Chris@19: normalization of the transform (the constant factor in front) and the Chris@19: sign of the complex exponent. We begin by presenting the Chris@19: one-dimensional (1d) transform definitions, and then give the Chris@19: straightforward extension to multi-dimensional transforms. Chris@19: Chris@19:
Chris@19: Chris@19: Chris@19: Chris@19: