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Re: GCC beaten by ICC in stupid trig test!

Robert Dewar wrote: 
Indeed if any programmer writes sin**2+cos**2, one can assume that the
intention is precisely to get the computed value that may not be 1.0. If
the programmer wants 1.0, they can write it explicitly!

Mathematical identities provide good tests of numerical accuracy; I have found instances where certain compilers do *not* compute "sin**2+cos**2" as equal to 1, usually due to a poor implementation of sin and cos.

The actual line of code in question was part of a testing spike, and it had no effect on the actual subject of the original post, and was not intended to be part of a production program.

--
Scott Robert Ladd
Coyote Gulch Productions (http://www.coyotegulch.com)
Software Invention for High-Performance Computing

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