I see, thanks! Here, I finally got it:
(%i19) M:matrix([1,2],[3,4]);
[ 1 2 ]
(%o19) [ ]
[ 3 4 ]
(%i20) get_lu_factors( lu_factor(M) );
[ 1 0 ] [ 1 0 ] [ 1 2 ]
(%o20) [[ ], [ ], [ ]]
[ 0 1 ] [ 3 1 ] [ 0 - 2 ]
(%i21)
--
Dotan Cohen
http://what-is-what.com
http://gibberish.co.il