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vForce performance vis-a-vis std C functions
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vForce performance vis-a-vis std C functions



I hopes of accelerating some standard C functions, I've run a few timing experiments to assess vForce.h function performance.  The results are disappointing.

- Comparing the time to run vvsqrt( ) on a 10000 point data file to a simple for( ) loop,
i.e., for( ii=0; ii<10000; ii++ ) yy[ii] = sqrt[ii] , shows a very slight improvement
( ~23 nsec per input data pt. for vvsqrt vice ~24 nsec for the loop),
- Comparing the time to run vvsin( ) in similar fashion actually shows the loop to be better--
 ( ~39 nsec per data pt. for vvsin vice ~21 nsec for the loop).

(FYI,  tests were run under Xcode 3.2.3 on a MacPro w Dual-Core, 3 GHz Xeon processor.)

My questions are:
- Are these timing results consistent with expected vForce performance?
- If not, what does one need to do to get the expected performance?
- And, regardless, are there other considerations that would favor use of the vForce functions?

Don Thompson
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