Once Lipschitz continuously differentiable approximation to the
Heaviside(.,.) function.
See Example
Annex60.Utilities.Math.Examples.SmoothHeaviside.
function smoothHeaviside input Real x "Argument"; input Real delta "Parameter used for scaling"; output Real y "Result"; end smoothHeaviside;
spliceFunction with regStep.
This is for
issue 300.
smoothOrder = 1.