Re: Geometric average: how to compute it: best approach ?

pamela fluente a écrit :

So, assuming the above block recursive computation,
what is more advisable: using the multiplication with powers, or the
sum with the logarithm?

The first 2 are quite slow, but, on the other hand, the logarithm has
to be taken n times.

Which way should be better and accurate ?

-P


Perhaps combining multiplications (without powers!) and taking the logarithm after a fixed number of multiplications (to avoid the cost of a comparison) that doing something like :
log(X[0]*X[1]*...*X[19])+log(X[20]*X[21]*...*X[39])+...

This is detailed in my answer to your last post of yesterday.

Stopping my evangelism attempt now! :-)
Raymond
.

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