## not understanding max's log computation

Sep 16, 2009 at 2:23am

# not understanding max's log computation

Hi,

I’m trying to use [scale] to output logarithmically, but can’t really understand how it is calculating its output. If the exponential base value is very close to 1 (e.g. 1.005) the first number output is much higher than 0.

Maybe it’s a lack of understanding of maths on my part, but it seems to me as though the curve should still be starting at 0, even if it looked almost exactly like a straight line, then as the exponent gets higher the curve would develop and show itself more drastically.

So… why the big jump at 0? And what can I do to get a good scalable logarithmic curve?

Jay

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#45462
Sep 16, 2009 at 6:36am

There’s a common understanding among max users that scale is not suitable for logarithmic scaling. It doesn’t work. (As long as you ignore it’s fifth argument, it’s a fantastic object.) One of the ways of dealing with this is:

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johan

#163919
Sep 16, 2009 at 8:25pm

Also, check out the awesome (and free!) Litter Power Starter Pack:

http://www.bek.no/~pcastine/Litter/

The lp.scampf object has log/expo scaling which works perfectly!

#163920
Sep 16, 2009 at 11:34pm

thanks for these suggestions…

i guess i should say is that i’m trying to program dials which can be logarithmically controlled, to a user-defined degree (where 1 = linear). any suggestion?

#163921
Sep 17, 2009 at 7:49am

The example I posted before is exactly about this. The number 1 creates a straight line (that is a number very close to 1 like 1.000001). As this number grows, the curvature increases.

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johan

#163922
Sep 17, 2009 at 12:27pm

thanks, yeah after messing around with it for a while i figured that out!

#163923

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