if output = TRUE write a output to an Excel (.csv).
Value
data.frame(time,x) and plot of process.
Details
A process X satisfying : $$dX(t) = X(t)*(theta-(sigma^3-theta*r)*X(t)) * dt + sigma * X(t)^(3/2) * dW(t)$$
With X(t)*(theta-(sigma^3-theta*r)*X(t)) :drift coefficient and sigma * X(t)^(3/2) :diffusion coefficient, W(t) is Wiener process, discretization dt = (T-t0)/N.
The conditional distribution of this process is related to that of the Cox-Ingersoll-Ross (CIR) model.