dlyapchol
Solves discrete-time Lyapunov equations with a square-root solver.
Syntax
X = dlyapchol(A, B)
X = dlyapchol(A, B, E)
Inputs
- A
 - Real square matrix.
 - B
 - A real matrix.
 - E
 - Real square matrix.
 
Outputs
- X
 - A real matrix.
 
Examples
A = [-5.0           0        -5.0;
       0.5           0           0;
         0           0         0.5];
 B = [ 0.5           1         0.5;
       1.5           1           1;
         1           1         1.5];
 U1 = dlyapchol (A, B)U1 = [Matrix] 3 x 3
0.50000  1.50000  1.00000
1.00000  1.00000  1.00000
0.50000  1.00000  1.50000A = [-5.0           0        -5.0;
       0.5           0           0;
         0           0         0.5];
 B = [ 0.5           1         0.5;
       1.5           1           1;
         1           1         1.5];
		 
 E = [2           2           4;
      1           0           5;
      3           1           1];
	  
 U2 = dlyapchol (A, B, E)U2 = [Matrix] 3 x 3
0.50000  1.50000  1.00000
1.00000  1.00000  1.00000
0.50000  1.00000  0.00000Comments
R = dlyapchol(A, B) solves AU'UA' - U'U = -BB' (Lyapunov matrix equation).
X = dlyapchol(A, B, E) solves AU'UA' - EU'UE' = -B B' (Sylvester equation).
Based on the SLICOT library functions SB03OD and SG03BD.