-- -*- M2-comint -*- {* hash: 767943444 *}

i1 : S = QQ[a..f];

i2 : g = hyperGraph {a*b*c*d,c*e,e*f}

o2 = HyperGraph{edges => {{a, b, c, d}, {c, e}, {e, f}}}
                ring => S
                vertices => {a, b, c, d, e, f}

o2 : HyperGraph

i3 : incidenceMatrix g

o3 = | 1 0 0 |
     | 1 0 0 |
     | 1 1 0 |
     | 1 0 0 |
     | 0 1 1 |
     | 0 0 1 |

              6        3
o3 : Matrix ZZ  <--- ZZ

i4 : T = QQ[f,e,d,c,b,a];

i5 : h = hyperGraph {a*b*c*d,c*e,e*f}

o5 = HyperGraph{edges => {{f, e}, {e, c}, {d, c, b, a}}}
                ring => T
                vertices => {f, e, d, c, b, a}

o5 : HyperGraph

i6 : incidenceMatrix h -- although the same graph, matrix is different since variables have different ordering

o6 = | 1 0 0 |
     | 1 1 0 |
     | 0 0 1 |
     | 0 1 1 |
     | 0 0 1 |
     | 0 0 1 |

              6        3
o6 : Matrix ZZ  <--- ZZ

i7 :