I was reading this lovley post [inconvergent.net] by Anders Hoff about how to control random numbers and I thought I'd try out some of the ideas in Houdini.

Then I realised my imaginiation far outstrips my skills. Even the very first section ('Random Node') I struggle with. I did create a Attribute Vop setup (and Solver version) which did begin to do what I wanted (I will upload when I get to my main machine) but I think there are much more elegant ways to do this. I used a mix node to animate the points but presumably subraction is better.

I would be interested in seeing how to do some of this stuff in VOPs or maybe VEX. And really what the best approach is. When it comes to using memory I guess the solver or particles are best as they build on previous values.

Really any pointers/examples or general thoughts on how to approach basic coding stuff like this would be appreciated.

Thanks,
Simon

Does this work for you?

Parameters to change values are on wave node in CHOP net.

Two of those variables in order to take effect must have the Python Source Editor Applied and Accept button clicked for new changes.

The magnitude parameter doesn't need this for changes.

This might help:

Ah thanks both. I will have to google the Python Source Editor.
And thanks Matt. This sorta makes sense but I will have to study. It's kind of simple but still melts my head. Much appreciated.

This might help too:

http://www.tokeru.com/cgwiki/index.php?title=The_solver_sop [tokeru.com]