function xprime = mcmc_lorenz(t,x,p);
%LORENZ: Computes the derivatives involved in solving the
%Lorenz equations.
sig=p(1); beta=p(2); rho=p(3);
xprime=[-sig*x(1) + sig*x(2); rho*x(1) - x(2) - x(1)*x(3); -beta*x(3) + x(1)*x(2)];