-- -*- M2-comint -*- {* hash: 2013110081 *}

i1 : R = QQ[a..d];

i2 : f = matrix{{0,a^2-b*c},{c,d}}

o2 = | 0 a2-bc |
     | c d     |

             2       2
o2 : Matrix R  <--- R

i3 : leadTerm f

o3 = | 0 a2 |
     | c 0  |

             2       2
o3 : Matrix R  <--- R

i4 : R = ZZ[a..d][x,y,z];

i5 : f = matrix{{0,(a+b)*x^2},{c*x, (b+c)*y}}

o5 = | 0  x2a+x2b |
     | xc yb+yc   |

             2       2
o5 : Matrix R  <--- R

i6 : leadTerm f

o6 = | 0  x2a |
     | xc 0   |

             2       2
o6 : Matrix R  <--- R

i7 :