Example

> a = triu(rand(4,4))
 a =
    0.807      0.253      0.216      0.762  
        0      0.339     0.0222      0.717  
        0          0      0.356     0.0606  
        0          0          0       0.78  
> b = triu(rand(4,4))
 b =
    0.324      0.156       0.37      0.743  
        0      0.133       0.81      0.705  
        0          0      0.909      0.621  
        0          0          0      0.845
> c = diag(rand(1,4))
 c =
    0.845          0          0          0  
        0      0.401          0          0  
        0          0      0.341          0  
        0          0          0      0.623  
> x = sylv(a,b,c)
 x =
   -0.747      0.353    -0.0535      0.294  
       -0     -0.849      0.556      0.443  
       -0         -0      -0.27      0.159  
       -0         -0         -0     -0.383  
> a*x+x*b + c
-1.11e-16  -5.55e-17          0  -5.55e-17  
        0          0   5.55e-17          0  
        0          0          0          0  
        0          0          0          0