Discrete Autoregressive Model DAR(1)

DAR (p), generates a stationary sequence of discrete random variables with an arbitrary probability distribution and with an autocorrelation structure similar to that of an Autoregressive model. DAR (1) is a special case of a DAR (p) and is defined as follows: DAR (1) process is a Markov Chain with discrete state space S and transition matrix : P = ρ I + (1-ρ) Where ρ is a autocorrelation coefficient, I is the identity matrix and Q is a matrix with = π (j) for i,j ? S I need the code for DAR(1) model