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Re: Is Matrix inversion O(N^3)?

Started by Unknown May 14, 2004
In article <sxdfza4qc4q.fsf@edgedsp4.rtp.ericsson.se> Raymond Toy <toy@rtp.ericsson.se> writes:
...
 > But I do still think we when we compute estimates of costs, MIPS,
 > cycles, whatever, we tend to ignore things like table lookups,
 > additions, etc, and assume they are free, compared to multiplication,
 > when in fact they can be even more expensive.

Well, if somebody does that he is wrong.  There are very many processors
(and not only DSP's) where a floating point multiply takes as many
cycles as a floating point addition.  Vector processors are of this
kind.  And the first one I did use with this feature was a CDC Cyber,
back in the seventies.
-- 
dik t. winter, cwi, kruislaan 413, 1098 sj  amsterdam, nederland, +31205924131
home: bovenover 215, 1025 jn  amsterdam, nederland; http://www.cwi.nl/~dik/