sylv

sylv — Sylvester equation.

Calling sequence

sylv(A,B,C,flag)

`A,B,C`	: three real matrices of appropriate dimensions.
`flag`	character string (`'c'` or `'d'`)

X = sylv(A,B,C,'c') computes X, solution of the "continuous time" Sylvester equation



A*X+X*B=C

X=sylv(A,B,C,'d') computes X, solution of the "discrete time" Sylvester equation



A*X*B-X=C



A=rand(4,4);C=rand(4,3);B=rand(3,3);
X = sylv(A,B,C,'c');
norm(A*X+X*B-C)
X=sylv(A,B,C,'d') 
norm(A*X*B-X-C)