Bug in geomean()

[kyfsympsn]

Hi,

Think I've noticed a big in the geomean(x) function (which can be also
written as mean(x,"g"))

In matlab, the following code:
  x = rand(1000,1);
  y=geomean(x)
  z=exp(mean(log(x)))

...will give the same value for y and z (roughly 0.3664)

However in octave y =0!!

I think octave is probably calculating the geometric mean by multiply all
values of x (i.e. prod(x)) and then taking the nth root. Mathemaically this
is identical to exp(mean(log(x))), but programmatically prod(x) will give a
very small number and so it returns zero (or very large number if the x's
are greater than 1, hence will return Inf)

Thanks
Keith 



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