log2() Problem

[amarg]

Hi all,

I want to use the function log2(). In my system this function is in sunmath.h. But i don't think this file is in every system.

Is there any standard file for ANSI-C where i can find the log2().


Regards,
Amar

 

[Salem]

Just use the identity

loga(b) = logx(b) / logx(a);

So long as you have the log function in one base, you can calculate logs in any other base.



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[amarg]

Thanks for your reply. I was using that formula.

I just want to know log2() function exist in math.h or not.

In Linux log2() is in math.h but on the sun machine it is not in math.h.

Regards,

 

[Salem]

log2 isn't a standard function, so it's availability will vary

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