AWK - Re: pow(x,y) function

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Re: pow(x,y) function

E. Rosten

2004-09-20, 8:56 pm

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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