i1 : R = QQ[a..d];
i2 : diagonalMatrix{a,b,c,3/4} o2 = | a 0 0 0 | | 0 b 0 0 | | 0 0 c 0 | | 0 0 0 3/4 | 4 4 o2 : Matrix R <--- R
i3 : diagonalMatrix(R,{1,2,3}) o3 = | 1 0 0 | | 0 2 0 | | 0 0 3 | 3 3 o3 : Matrix R <--- R