Ben,

You hit the nail on its head! Thanks much! That is (mostly) what I am after, but I can work around that.

Having both points on the same plane is no problem. I will copy and rotate the sine later on.

The sliders would make the script a bit easier to handle, because I don't know in advance how many half-cycles at what amplitude I want, I change the values and look at the result until I am happy. A slider would be more direct: Instead of clearing the field, entering a number, hitting enter, simply dragging a slider or pushing Up/Down arrows would be more natural.

But again, thank you very much! Having the sine like that will allow me to continue.

Ditto