Re: pow(x,y) function

Vikas Agnihotri wrote:
> gawk 3.1.0 on Solaris 8
>
> I was surprised that there is no built-in pow(x,y) function.
>
> Can someone help me write one? If I remember my high school math right,
> there is a way to write pow(x,y) using the builtin log/exp functions?
>
> Help? Thanks


Here's the hard way:

ln(pow(a,b)) = b * ln(a)

therefore pow(a,b) = exp(b*log(a))


Proof is left as an exercist to the reader...


Of course, you can always use the builtin function:

a^b

:-)


-Ed





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