I've got a setup below where I randomise some audio by using a stamp function in chops. It works as expected.

But what I can't seem to do is get it work when I use a function like $F or $T.
Currently floor(rand($I)*4) works. Where as something like floor((sin($F*3)*2)+1) won't.

Am I limited to certain functions?
If so what would be an elegant way to cycle (in modulo fashion %) through a series of samples?

Thanks
Simon

$F and $T always refer to the global frame and time as noted on the playbar, and not the CHOP sample time or frame. $I is the current CHOP sample, which is why it works.

Thanks Twod.

So it possible to feed in any functions other than the native CHOP ones to a stamp function?

As far as I understand, you can feed anything into a stamp. You just got an unexpected result, because you took information from the wrong frame of reference for the task.
- Also note: Local variables are only available on the nodes that have them, but if you can get the data there, you can use it anywhere down the line.

DASD
As far as I understand, you can feed anything into a stamp. You just got an unexpected result, because you took information from the wrong frame of reference for the task.
- Also note: Local variables are only available on the nodes that have them, but if you can get the data there, you can use it anywhere down the line.

Yep, I'm fairly new to Houdini so still getting my head around the basics.
There probably is fairly easy ways to do what I want to do but I've yet to stumble on them.

$F/$T and so on do work in Chops for creating channels and so on but not in the Copy/Stamp.

As mentioned originally I'd like a way to cycle through the three oscillators with the timing based on the trigger. The logic is easy, just count the trigger hits and use a Modulos but I can't see an easy way to apply this.

Maybe you need to use
http://www.sidefx.com/docs/houdini15.0/expressions/chopci [sidefx.com]
or
http://www.sidefx.com/docs/houdini15.0/expressions/chopi [sidefx.com]
or something like that…
The idea would be to use such an expression in a parameter of your target. (By target I mean the thing you want to influence by the data from the CHOPs)

DASD
Maybe you need to use
http://www.sidefx.com/docs/houdini15.0/expressions/chopci [sidefx.com]
or
http://www.sidefx.com/docs/houdini15.0/expressions/chopi [sidefx.com]
or something like that…
The idea would be to use such an expression in a parameter of your target. (By target I mean the thing you want to influence by the data from the CHOPs)

Ah yes. Got it working. Lovely, thanks loads