I was watching the Recursive Voronoi tutorial. https://www.sidefx.com/tutorials/recursive-voronoi/ [www.sidefx.com]

Part of the expression he used is the detail expression which I looked up and it sounds pretty straight forward. However, part of the expression he used is “(detail(-1,”iteration“,0)”. My question is in regard to the -1. Why -1? Thanks for helping me understand what's happening here.

-1 refers to accessing the iteration via the first spare input. So you add a spare input via the gear icon that you use to set parameters and stuff like that. You can add more than one spare input and access them with -2, -3, -4 etc.

Some info on using spare inputs here. http://www.tokeru.com/cgwiki/index.php?title=ForLoops [www.tokeru.com]