If I am right, the original version was a sinusoidally-modulated (nonstationary) Bernoulli process. I want 3 possible values, not 2, which makes it a "Bernoulli scheme" http://en.wikipedia.org/wiki/Bernoulli_scheme Not sure how to the create a sinusoidally modulated Bernoulli scheme with values 0, 0.5, 1. Bill