if !struct_contains(p_o,"x_0")
    p_o.x_0 = zeros(n_x,1);
  endif
  
  if !struct_contains(p_o,"method")
    ##p_o.method = "continuous";
    ##p_o.method = "intermittent";
    p_o.method = "remote";
  endif
  

  ## Check w.
  [n_w,m_w] = size(w);
  if ( (n_w!=n_y) || (m_w!=1) )
    error(sprintf("ppp_lin_run: w must a column vector with %i elements",n_y));

    A_ud = expm(p_c.A_u*dt);	# Discrete-time input transition
    if (ControlType==2)		# 
      [L, M, P, obs_poles] = dlqe(Ad,G,C,sigma_x,Sigma);
    else
      L = zeros(n_x,n_y);
      obs_poles = eig(Ad);
    endif
  elseif strcmp(p_o.method, "remote")
    L = zeros(n_x,n_y);
    obs_poles = [];
  else
    error(sprintf("Observer method ""%s"" unknown", p_o.method));
  endif
  
  ## Display the poles
  obs_poles

	t_sim = [1:p_c.N]*dt;	# Simulation time points
	[yi,ui,xsi] = ppp_ystar(A,B,C,D,x,p_c.A_u,U,t_sim); # Simulate
	x = xsi(:,p_c.N);	# Current state (for next time)
	ti  = [(i-1)*p_c.N:i*p_c.N-1]*dt; 
	y_i = yi(1);	# Current output
	t_i = ti(1);
      else			# The real thing
	if strcmp(p_o.method, "remote")
	  [t_i,y_i,X] = ppp_put_get_X(U); # Remote-state interface
	  u_i = X(3);		# Integrated control is third state
	else
	  [t_i,y_i,u_i] = ppp_put_get(U); # Generic interface to real-time
	endif
      endif

      ## Observer
      if strcmp(p_o.method, "intermittent")
	[x_est y_est y_new, e_est] = ppp_int_obs \
	    (x_est,y_i,U,A,B,C,D,p_c.A_u,p_c.delta_ol,L);
      elseif strcmp(p_o.method, "continuous")
	Ui = U;			# U at sub intervals
	for k = 1:p_c.N
	  [x_est y_est y_new e_est] = ppp_int_obs \
	      (x_est,yi(:,k),Ui,A,B,C,D,p_c.A_u,dt,L);
	  Ui = A_ud'*Ui;
	  y_e = [y_e; y_new'];
	  e_e = [e_e; e_est'];
	endfor
      elseif strcmp(p_o.method, "remote")
	## predict from remote state (with zero L)
	[x_est y_est y_new e_est] = ppp_int_obs \
	      (X,y_i,U,A,B,C,D,p_c.A_u,p_c.delta_ol,L);
      endif
      
      ##Control
      if ( (p_c.Tau_u==[])&&(p_c.Tau_y==[]) )
	U = K_w*w - K_x*x_est;
      else
	## Input constraints