Our usual frequency variable is in radians per second. However, certain Fourier theorems are undeniably simpler and more elegant when the frequency variable is chosen to be in cycles per second. The two are of course related by
As an example, is more compact than . On the other hand, it is nice to get rid of all normalization constants in the Fourier transform and its inverse:
The ``editorial policy'' for this book is this: Generally, is preferred, but is used when considerable simplification results.
Fourier Transform Notation