### 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

**all**of the following text. Then, in Max, select

*New From Clipboard*.

```
----------begin_max5_patcher----------
464.3ocuUFsaCBBEF9Z8ofv0cKBpUc2smikkEpRaYAgFEy5ZSe2GfRccw0Zr
ldCDOfG9++3.bz2CtRtmVCAu.dC34cz2yyFxDvq6aOXIYeNmTamFbMWJZJgK
ZGhUXCJW84SnDWvRlfUpmidDzyAcA0+DSvoJaVPcAWKEJAojZSxqULB2kicD
U9VlXyGUzbUq9vHrNafDSNAwAlVrtE7d+JHaTtk.2EsMj56cz1rXL.QAW.fq
HhMvy+sQJ0rC1YYVHSzS99llEiDMB5WZP3bfht2Jb3AtNgofMUxlcCvsL3PD
BOEBkkYfBBY6RRlJgLv4Q.l5bBmBPV5DnaSLkKgCfnzAQzxoinrXKnBw2.Qn
qWDMmLZUiRIECX9H30NAMfEWZsXTryaSygcmNluc6lCLyN8.NDOem.Z89xTK
Axtg2Cup2Wz2yDy6dcYCWwp4rBZ0PWj5hUSUZdn+yVYY2J0mRtzOipjn6hgn
PSWnqz3tuZnGCo+hB1ggbl3uOrXElI9knoV1Tk6V.2KIfdoUPqULAQwzGO5m
jtPBDedNaYEET6vAmeDpXmTuw0og+oRdrRRWhBviPQAOLEkNBFk8PUT1HTD5
gpnnQnH7cnH8Gm7+APr7eTC
-----------end_max5_patcher-----------
```

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:

**all**of the following text. Then, in Max, select

*New From Clipboard*.

```
----------begin_max5_patcher----------
529.3ocyVFrSiCCDF9bxSgkEGfUgRrSBD319RrWVPqbabKdUhcThinaQ7tu1
SRH.p0MUzF3hs7X2w+9alISe12COWslWiQ2g9Mxy6YeOOvj0fW2ZObAa8hbV
MbLrj+jZ9ewAsao4q0f4efHzal0adoRpqEa31sHjYgclkMEpFcNWCthzYs0j
9ek7VcfWlqXFu9P29kL8hGExU+ohuP2dDRD03TDI4Z6TLLRCmE95uQjApxnz
KIz2pJIq.tF7u3UYLICOHMgrWYTqsW78sCAeNtb0WBWBSAtD6jKjIgKFQa7w
AA.pa.DfvyYxUNAQTXHP.fCIgt3P5AiAxwK8futrBcdo5oyOaI896CNaI4hK
IWbkcoY93j2LpTltozHWrJ4qrTZSNZUkpo73jKYSibCl1hHxs.XRRbwknIgK
yazZkDeXA+8VpjBek35WqQ18qL9TWMzrQX9bYJJbqgX5NBwQNe5ACyBodDjn
cL4VWjX6sT9Ykfkezh1EM4ZQctHiWgOMo1TBz3LJtK2dWMJ5u9gHQZuEt17J
Mxt0uP1ise2fe1YpBbBbtP9w+9AnWq82ylZUS0h9WXeeczvEkwq0BISKLUHC
GJ5cm4QQVFG1tOSpPjUpL4EcZ.8vVCTiURIiPQeP1mZIY6xuWMkLoRxB.59n
DYRkT5HgD4akhhm7vF4aU4VzXJ2lTEEOBE8Yp+MKdw++sEoHnA
-----------end_max5_patcher-----------
```

_

johan

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!

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?

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.

_

johan

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

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