[PD] Newbie: Dollar sign explanation needed

[Andy Farnell]

Hi Afif,

The dollar can have more than one meaning depending on where it is used.

When it is in a message box, like [1 $1 3 $2( it behaves as a substitution
operator. The nth element of a list will be substituted in the $n position
and the list message is passed on. So, if a two element list 2, 4 was
presented to the message box above the result would be a four element
list 1, 2, 3, 4


When it is used in other object boxes in the form $1 or $2 etc it becomes
the $nth parameter of an abstraction. In other words, if you create an
abstraction (separate pd file) called [myabs] and create an instance like
[myabs 10 20 30] then inside  that instance $1 will have a value of 10, 
$2 a value of 20 and $3 will equal 30.

A special use is where you declare $0. This always has a unique value
per patch (or abstraction instance). It can be used to prefix a variable
name so that it is unique. For example, arrays must always have a unique
name. You can create an array called $0-a in an abstraction, and if you
make several copies of that abstraction the array names will not clash.








On Sat, 25 Oct 2008 15:15:28 +0100
"Arif Driessen" <arifd86 at gmail.com> wrote:

> Hello all.
> 
> Since starting Uni this year I have gotten really into Pd! I'm still reading
> up and learning the basics but have tried and tried to get my head around
> the $ parameter (parameter?) but can't
> 
> Can someone break it down into a very basic explanation so I can take that
> with me to the help files for further understanding.
> 
> As I see it, $ pretty much denotes storage of a variable, either float or
> symbol, and works only locally. When added to an object it means: take
> incoming value and store it under $1 (or $2 e.t.c) for recall later. If
> there is a series of in incoming values $1 will always refer to the first
> value and $2 to the second. Sometimes you don't want to recall it, but need
> to tell the object to store a value in order to process it with the very
> next action, such as in
> 
> OBJECT: openpanel > MESSAGE: read $1 destination > OBJECT: soundfiler
> 
> Am I right, somewhat right, or dangerously wrong?
> 
> And lastly I get this in the Pd window everytime it starts up (Pd extended
> on Mac), is that heathly?:
> 
> libdir loader $Revision: 1.8 $
>     written by Hans-Christoph Steiner <hans at at.or.at>
>     compiled on Jul 29 2008 at 04:03:05
>     compiled against Pd version 0.40.3.extended
> /Applications/Pure
> Data/Pd-extended.app/Contents/Resources/extra/Gem/Gem.pd_darwin:
> dlopen(/Applications/Pure
> Data/Pd-extended.app/Contents/Resources/extra/Gem/Gem.pd_darwin, 10):
> Library not loaded: /usr/X11R6/lib/libfreetype.6.dylib
>   Referenced from: /Applications/Pure
> Data/Pd-extended.app/Contents/Resources/extra/Gem/Gem.pd_darwin
>   Reason: image not found
> Gem: can't load library
> libdir_loader: added 'cyclone' to the global objectclass path
> libdir_loader: added 'zexy' to the global objectclass path
> libdir_loader: added 'creb' to the global objectclass path
> libdir_loader: added 'cxc' to the global objectclass path
> libdir_loader: added 'iemlib' to the global objectclass path
> libdir_loader: added 'list-abs' to the global objectclass path
> libdir_loader: added 'mapping' to the global objectclass path
> libdir_loader: added 'markex' to the global objectclass path
> libdir_loader: added 'maxlib' to the global objectclass path
> libdir_loader: added 'memento' to the global objectclass path
> libdir_loader: added 'mjlib' to the global objectclass path
> libdir_loader: added 'motex' to the global objectclass path
> libdir_loader: added 'oscx' to the global objectclass path
> libdir_loader: added 'pddp' to the global objectclass path
> libdir_loader: added 'pdogg' to the global objectclass path
> libdir_loader: added 'pixeltango' to the global objectclass path
> libdir_loader: added 'pmpd' to the global objectclass path
> libdir_loader: added 'rradical' to the global objectclass path
> libdir_loader: added 'sigpack' to the global objectclass path
> libdir_loader: added 'smlib' to the global objectclass path
> libdir_loader: added 'toxy' to the global objectclass path
> libdir_loader: added 'unauthorized' to the global objectclass path
> libdir_loader: added 'pan' to the global objectclass path
> libdir_loader: added 'freeverb' to the global objectclass path
> libdir_loader: added 'hcs' to the global objectclass path
> libdir_loader: added 'jmmmp' to the global objectclass path
> libdir_loader: added 'ext13' to the global objectclass path
> libdir_loader: added 'ggee' to the global objectclass path
> libdir_loader: added 'flib' to the global objectclass path
> libdir_loader: added 'ekext' to the global objectclass path
> libdir_loader: added 'flatspace' to the global objectclass path
> /Applications/Pure
> Data/Pd-extended.app/Contents/Resources/extra/pdp.pd_darwin:
> dlopen(/Applications/Pure
> Data/Pd-extended.app/Contents/Resources/extra/pdp.pd_darwin, 10): Library
> not loaded: /usr/X11R6/lib/libX11.6.dylib
>   Referenced from: /Applications/Pure
> Data/Pd-extended.app/Contents/Resources/extra/pdp.pd_darwin
>   Reason: image not found
> pdp: can't load library
> /Applications/Pure
> Data/Pd-extended.app/Contents/Resources/extra/pidip.pd_darwin:
> dlopen(/Applications/Pure
> Data/Pd-extended.app/Contents/Resources/extra/pidip.pd_darwin, 10): Library
> not loaded: /usr/X11R6/lib/libX11.6.dylib
>   Referenced from: /Applications/Pure
> Data/Pd-extended.app/Contents/Resources/extra/pidip.pd_darwin
>   Reason: image not found
> pidip: can't load library
> 
> 
> 
> ///////////
> 
> Thanks so much everyone.
> 


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