<html>
<head>
<meta content="text/html; charset=utf-8" http-equiv="Content-Type">
</head>
<body text="#000000" bgcolor="#FFFFFF">
You're using the [scale] formula from @classic_mode in Max7, which
exists for compatibility with IRCAM, but it's clearly wrong.
(There's no way mapping 13.3 from 0-127 to -1 to 1 should result in
something so close to -1. Just try a few different exponents and
you'll see that there's a bug in the Max code. And there are lots of
bug reports out there about it.)<br>
<br>
That's why they introduced an alternate mode for [scale] in Max,
which can be switch in the Inspector.<br>
<br>
For non-classic (modern) mode, the documentation gives you this
equation:<br>
<br>
<meta http-equiv="content-type" content="text/html; charset=utf-8">
<span style="color: rgb(51, 51, 51); font-family: Lato, sans-serif;
font-size: 13px; font-style: normal; font-variant: normal;
font-weight: normal; letter-spacing: normal; line-height:
18.5714302062988px; orphans: auto; text-align: start; text-indent:
0px; text-transform: none; white-space: normal; widows: 1;
word-spacing: 0px; -webkit-text-stroke-width: 0px; display: inline
!important; float: none; background-color: rgb(255, 255, 255);">((x-in_low)/(in_high-in_low)
== 0) ? out_low : (((x-in_low)/(in_high-in_low)) > 0) ?
(out_low + (out_high-out_low) * ((x-in_low)/(in_high-in_low))^exp)
: ( out_low + (out_high-out_low) *
-((((-x+in_low)/(in_high-in_low)))^(exp)))</span><br>
<br>
Translated to expr as:<br>
<br>
[expr if ((($f1-in_low)/(in_high-in_low)==0), out_low, if
((($f1-in_low)/(in_high-in_low)>0),
out_low+(out_high-out_low)*pow(($f1-in_low)/(in_high-in_low),
power),
out_low+(out_high-out_low)*-1*pow((-1*$f1+in_low)/(in_high-in_low),
power)))]<br>
<br>
Switch off classic mode in the inspector in Max7, and you get the
same result as expr above, the very sensible -0.817072.<br>
<br>
Joel<br>
<br>
<div class="moz-cite-prefix">On 06/19/2015 05:39 PM, Alexandre
Torres Porres wrote:<br>
</div>
<blockquote
cite="mid:CAEAsFmjirTNhFb9LfJxHFo7CtiFzWkDY2pFFzHmgj8Y7S6y-6w@mail.gmail.com"
type="cite">
<div dir="ltr">
<p style="margin:0px 0px 6px">Howdy, so I'm cloning the scale
object from Max, to make an object and include in the cyclone
library. It converts range input (low_in / high_in) to a range
output (low_out / high_out). It has a logarithmic curve for
rescaling according to a fifth argument/inlet. I did copy into
expr the formula described in the reference of Max6/7 (max's 5
was just wrong, copied from [linedrive]) - well, it didn't
work! Would anyone know if I'm doing something wrong or if the
reference is not telling the truth?</p>
<p style="margin:6px 0px">The formula, as described in the
reference is: (out_low + (out_<span class=""
style="display:inline">high-out_low) * ( (out_high -
out_low) * exp(-1 * (in_high-in_low) * log(power)) * exp(x *
log(power)) ))</span></p>
<p style="margin:6px 0px"><span class="" style="display:inline"><br>
</span></p>
<div class="" style="display:inline">
<p style="margin:0px 0px
6px;color:rgb(20,24,35);font-family:helvetica,arial,sans-serif;font-size:14px;line-height:15.4559993743896px">Here's
my patch with that formula into expr. The output with the
parameters I have should be -0.997347 - as that's the output
I get in Max. But instead, it's giving -0.994694...</p>
<p style="margin:0px 0px
6px;color:rgb(20,24,35);font-family:helvetica,arial,sans-serif;font-size:14px;line-height:15.4559993743896px"><br>
</p>
<p style="margin:0px 0px
6px;color:rgb(20,24,35);font-family:helvetica,arial,sans-serif;font-size:14px;line-height:15.4559993743896px">thanks</p>
<p style="margin:0px 0px
6px;color:rgb(20,24,35);font-family:helvetica,arial,sans-serif;font-size:14px;line-height:15.4559993743896px"><br>
</p>
<p style="margin:0px 0px
6px;color:rgb(20,24,35);font-family:helvetica,arial,sans-serif;font-size:14px;line-height:15.4559993743896px"><br>
</p>
<p style="margin:0px 0px
6px;color:rgb(20,24,35);font-family:helvetica,arial,sans-serif;font-size:14px;line-height:15.4559993743896px"><br>
</p>
<p style="margin:0px 0px
6px;color:rgb(20,24,35);font-family:helvetica,arial,sans-serif;font-size:14px;line-height:15.4559993743896px">=================</p>
<p style="margin:0px 0px
6px;color:rgb(20,24,35);font-family:helvetica,arial,sans-serif;font-size:14px;line-height:15.4559993743896px"><br>
</p>
<p style="margin:0px 0px 6px"><font color="#141823"
face="helvetica, arial, sans-serif"><span
style="font-size:14px;line-height:15.456000328064px">#N
canvas 24 23 488 340 10;</span></font></p>
<p style="margin:0px 0px 6px"><font color="#141823"
face="helvetica, arial, sans-serif"><span
style="font-size:14px;line-height:15.456000328064px">#X
obj 215 154 v out_low;</span></font></p>
<p style="margin:0px 0px 6px"><font color="#141823"
face="helvetica, arial, sans-serif"><span
style="font-size:14px;line-height:15.456000328064px">#X
obj 233 132 v out_high;</span></font></p>
<p style="margin:0px 0px 6px"><font color="#141823"
face="helvetica, arial, sans-serif"><span
style="font-size:14px;line-height:15.456000328064px">#X
obj 288 110 v power;</span></font></p>
<p style="margin:0px 0px 6px"><font color="#141823"
face="helvetica, arial, sans-serif"><span
style="font-size:14px;line-height:15.456000328064px">#X
obj 152 130 v in_high;</span></font></p>
<p style="margin:0px 0px 6px"><font color="#141823"
face="helvetica, arial, sans-serif"><span
style="font-size:14px;line-height:15.456000328064px">#X
obj 115 153 v in_low;</span></font></p>
<p style="margin:0px 0px 6px"><font color="#141823"
face="helvetica, arial, sans-serif"><span
style="font-size:14px;line-height:15.456000328064px">#X
floatatom 58 248 0 0 0 0 - - -;</span></font></p>
<p style="margin:0px 0px 6px"><font color="#141823"
face="helvetica, arial, sans-serif"><span
style="font-size:14px;line-height:15.456000328064px">#X
obj 58 197 expr (out_low + (out_high-out_low) * (
(out_high - out_low)</span></font></p>
<p style="margin:0px 0px 6px"><font color="#141823"
face="helvetica, arial, sans-serif"><span
style="font-size:14px;line-height:15.456000328064px">*
exp(-1*(in_high-in_low)*log(power)) *
exp($f1*log(power)) ));</span></font></p>
<p style="margin:0px 0px 6px"><font color="#141823"
face="helvetica, arial, sans-serif"><span
style="font-size:14px;line-height:15.456000328064px">#X
msg 115 102 0;</span></font></p>
<p style="margin:0px 0px 6px"><font color="#141823"
face="helvetica, arial, sans-serif"><span
style="font-size:14px;line-height:15.456000328064px">#X
msg 152 102 127;</span></font></p>
<p style="margin:0px 0px 6px"><font color="#141823"
face="helvetica, arial, sans-serif"><span
style="font-size:14px;line-height:15.456000328064px">#X
msg 215 99 -1;</span></font></p>
<p style="margin:0px 0px 6px"><font color="#141823"
face="helvetica, arial, sans-serif"><span
style="font-size:14px;line-height:15.456000328064px">#X
msg 249 97 1;</span></font></p>
<p style="margin:0px 0px 6px"><font color="#141823"
face="helvetica, arial, sans-serif"><span
style="font-size:14px;line-height:15.456000328064px">#X
msg 288 86 1.06;</span></font></p>
<p style="margin:0px 0px 6px"><font color="#141823"
face="helvetica, arial, sans-serif"><span
style="font-size:14px;line-height:15.456000328064px">#X
obj 90 31 loadbang;</span></font></p>
<p style="margin:0px 0px 6px"><font color="#141823"
face="helvetica, arial, sans-serif"><span
style="font-size:14px;line-height:15.456000328064px">#X
obj 90 60 t b b;</span></font></p>
<p style="margin:0px 0px 6px"><font color="#141823"
face="helvetica, arial, sans-serif"><span
style="font-size:14px;line-height:15.456000328064px">#X
msg 58 107 13.3;</span></font></p>
<p style="margin:0px 0px 6px"><font color="#141823"
face="helvetica, arial, sans-serif"><span
style="font-size:14px;line-height:15.456000328064px">#X
connect 6 0 5 0;</span></font></p>
<p style="margin:0px 0px 6px"><font color="#141823"
face="helvetica, arial, sans-serif"><span
style="font-size:14px;line-height:15.456000328064px">#X
connect 7 0 4 0;</span></font></p>
<p style="margin:0px 0px 6px"><font color="#141823"
face="helvetica, arial, sans-serif"><span
style="font-size:14px;line-height:15.456000328064px">#X
connect 8 0 3 0;</span></font></p>
<p style="margin:0px 0px 6px"><font color="#141823"
face="helvetica, arial, sans-serif"><span
style="font-size:14px;line-height:15.456000328064px">#X
connect 9 0 0 0;</span></font></p>
<p style="margin:0px 0px 6px"><font color="#141823"
face="helvetica, arial, sans-serif"><span
style="font-size:14px;line-height:15.456000328064px">#X
connect 10 0 1 0;</span></font></p>
<p style="margin:0px 0px 6px"><font color="#141823"
face="helvetica, arial, sans-serif"><span
style="font-size:14px;line-height:15.456000328064px">#X
connect 11 0 2 0;</span></font></p>
<p style="margin:0px 0px 6px"><font color="#141823"
face="helvetica, arial, sans-serif"><span
style="font-size:14px;line-height:15.456000328064px">#X
connect 12 0 13 0;</span></font></p>
<p style="margin:0px 0px 6px"><font color="#141823"
face="helvetica, arial, sans-serif"><span
style="font-size:14px;line-height:15.456000328064px">#X
connect 13 0 14 0;</span></font></p>
<p style="margin:0px 0px 6px"><font color="#141823"
face="helvetica, arial, sans-serif"><span
style="font-size:14px;line-height:15.456000328064px">#X
connect 13 1 11 0;</span></font></p>
<p style="margin:0px 0px 6px"><font color="#141823"
face="helvetica, arial, sans-serif"><span
style="font-size:14px;line-height:15.456000328064px">#X
connect 13 1 10 0;</span></font></p>
<p style="margin:0px 0px 6px"><font color="#141823"
face="helvetica, arial, sans-serif"><span
style="font-size:14px;line-height:15.456000328064px">#X
connect 13 1 9 0;</span></font></p>
<p style="margin:0px 0px 6px"><font color="#141823"
face="helvetica, arial, sans-serif"><span
style="font-size:14px;line-height:15.456000328064px">#X
connect 13 1 8 0;</span></font></p>
<p style="margin:0px 0px 6px"><font color="#141823"
face="helvetica, arial, sans-serif"><span
style="font-size:14px;line-height:15.456000328064px">#X
connect 13 1 7 0;</span></font></p>
<p style="margin:0px 0px 6px"><font color="#141823"
face="helvetica, arial, sans-serif"><span
style="font-size:14px;line-height:15.456000328064px">#X
connect 14 0 6 0;</span></font></p>
<div><br>
</div>
</div>
</div>
<br>
<fieldset class="mimeAttachmentHeader"></fieldset>
<br>
<pre wrap="">_______________________________________________
<a class="moz-txt-link-abbreviated" href="mailto:Pd-list@lists.iem.at">Pd-list@lists.iem.at</a> mailing list
UNSUBSCRIBE and account-management -> <a class="moz-txt-link-freetext" href="http://lists.puredata.info/listinfo/pd-list">http://lists.puredata.info/listinfo/pd-list</a>
</pre>
</blockquote>
<br>
</body>
</html>