This method returns the $n \times{} n$ matrix of direct causal effect indeterminates. This matrix has the parameter $l_{(i,j)}$ in the $(i,j)$ position if there is a directed edge $i \to j$, and 0 otherwise. Note that this matrix is not symmetric. The documentation of gaussianRing further describes the indeterminates $l_{(i,j)}$.
i1 : G = mixedGraph(digraph {{b,{c,d}},{c,{d}}},bigraph {{a,d}})
o1 = MixedGraph{Bigraph => Bigraph{a => {d}} }
d => {a}
Digraph => Digraph{b => {c, d}}
c => {d}
d => {}
Graph => Graph{}
o1 : MixedGraph
|
i2 : R = gaussianRing G o2 = R o2 : PolynomialRing |
i3 : compactMatrixForm =false; |
i4 : directedEdgesMatrix R
o4 = | 0 0 0 0 |
| |
| 0 0 l l |
| b,c b,d |
| |
| 0 0 0 l |
| c,d |
| |
| 0 0 0 0 |
4 4
o4 : Matrix R <--- R
|
i5 : D = digraph{{a,b},{c,d}}
o5 = Digraph{a => {b}}
b => {}
c => {d}
d => {}
o5 : Digraph
|
i6 : directedEdgesMatrix gaussianRing D
o6 = | 0 0 0 0 |
| |
| 0 0 l l |
| b,c b,d |
| |
| 0 0 0 l |
| c,d |
| |
| 0 0 0 0 |
4 4
o6 : Matrix R <--- R
|
The object directedEdgesMatrix is a method function.