isShelling L
Determines if a list of faces is a shelling order of the simplicial complex generated by the list.
Let $S$ be the simplicial complex generated by the list of facets $L$. If $S$ is pure, then definition III.2.1 in [St] is used. That is, $L_1, .., L_n$ is a shelling order of $S$ if the difference in the $j$th and $j1$th subcomplex has a unique minimal face, for $2 \leq j \leq n$.
If $S$ is nonpure, then definition 2.1 in [BW1] is used. That is, $L_1, .., L_n$ is a shelling order if the intersection of the faces of the first $j1$ facets with the faces of the $L_j$ is pure and $dim L_j  1$dimensional.



The object isShelling is a method function.