Given matrix A.

[L,U,P] = lu(A); % calculate partial-pivoted LU decomposition of A

D = diag(diag(U)); % get diagonal matrix

U = DU; % the 'U' that is needed is really inv(D)*U

A = [1 2 3 ; 4 5 6 ; 7 8 9] ;
[L U P] = lu(A)   ; % calculate p-p LU decomp.

D = diag(diag(L)) ; % get diagonal matrix

L * D * U           % check left side
P * A               % check right