[PD] bandlimited oscillators: set of abstractions

IOhannes m zmoelnig zmoelnig at iem.at
Mon Mar 19 09:26:51 CET 2007

Steffen wrote:
> On 18/03/2007, at 11.37, Derek Holzer wrote:
>> I've had several students on both windows and OS X that had trouble  
>> with the [>~] object for various reasons. It can be replaced with  
>> [expr~ $v1 > $v2], which is what the [>~] abstraction uses.
> I saw that in the help patch for the abstraction. That help patches  
> says also that "you *cannot* use arguments with this version, like  
> [>~ 2.7]". Now i wonder if there is are Pd-technicalities that limits  
> to such behavior, since it's not implemented?

it is a problem with the use of [expr~] which allows either a signal on
an inlet or a float. you have to decide which one to use at creation time.
in zexy's [>~] abstraction, the decision has been made towards the
former case.

i currently do not know of a solution for this problem...
..., since the arguments of [expr~] cannot be changed dynamically;
..., since there is no way to tell from within an abstraction whether
there are arguments at all (my $@-patch fixes this);
..., since there is no way to change the abstraction's interface
dynamically based on arguments (my [initbang]-patch fixes this);

since zexy relies only on vanilla-pd, it cannot solve this problem in
it's abstraction set. for this very reason it still provides a binary
version of [>~].

but of course you can/should implement both [>~] and [>~ 0] directly
with [expr~], and then you have the freedom of choice.


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