🚀 go-pugleaf

In article <1992Sep7.110102.25536@bnr.co.uk>
  pgh@bnr.co.uk (Peter Hamer) writes:
>Serious question: so why not use the Hartley transform which does not
>introduce these redundancies in the first place?

Well, in at least some fields, (mine, for instance), the fundamental observable
actually starts in the Fourier plane.  We measure Fourier coefficients
directly, and reconstruct the image from them.  And, as someone else already
mentioned, it's really not all that painful to go from a real full plane to
a complex half plane.  There is a lot of bookkeeping that must go into our
programs, no matter which transform we use.  Keeping track of transform
direction just isn't that much added complexity.  Finally, is or isn't the
FHT kosher to use these days?  When first it came out, Stanford was trying
to milk it for all it was worth.  I actually sent for one of their information
packets.  They wanted something like 5% of gross sales per copy or some hefty
minimum, for any program which used the transform.  That all by itself was
a good reason not to use the transform at the time, when it doesn't really
provide much more in the way of functionality than the FFT.

-- 
| Daniel Briggs  (dbriggs@nrao.edu)                      |        USPA B-14993
| New Mexico Tech / National Radio Astronomy Observatory |            DoD #387
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