Online Help

datatype=type

Specifies a datatype for the generated Matrix as described in rtable . The default is datatype=anything.

order=one of C_order or Fortran_order

Specifies the order of the generated Matrix. The default is order=C_order.

shape=name or list of names

Specifies the storage allocation for Matrix entries. Must be a name or list of names specifying one or more built-in or user-defined indexing functions . The default is shape=symmetric if G is undirected and shape=[] if G is directed.

storage=name

Specifies the storage mode . The default is storage=sparse if the number of edges is much smaller than the square of the number of vertices; otherwise, it is storage=triangular[upper] if G is undirected and storage=rectangular if G is directed.

The AdjacencyMatrix command returns the adjacency matrix of a graph G whose rows and columns are indexed by the vertices. The entry $i,j$ of this matrix is 1 if there is an edge from vertex i to vertex j and 0 otherwise.

The optional parameter L is a list of three elements specifying alternate special-purpose values for the entries of the adjacency matrix. If specified, the generated matrix has the following properties:

A[i,j] = L[1] when there is an edge from i to j in G

A[i,j] = L[2] when there is no edge from i to j in G

A[i,i] = L[3] along the diagonal

The default behavior corresponds to specifying the list [1,0,0].

The default output is an n by n Matrix with the following properties:

If G is directed or undirected: datatype=anything and order=C_order

If G is undirected: shape=symmetric, storage=triangular[upper],

If G is directed: storage=rectangular, shape=[]

If G is sparse, i.e., |E| << |V|^2 then storage=sparse is used.

$\mathrm{with}\left(\mathrm{GraphTheory}\right)\&colon;$

$G≔\mathrm{Graph}\left(\left[1\&comma;2\&comma;3\&comma;4\right]\&comma;\mathrm{Trail}\left(1\&comma;2\&comma;3\&comma;4\&comma;1\right)\right)$

$G≔\mathrm{Graph\; 1:\; an\; undirected\; graph\; with\; 4\; vertices\; and\; 4\; edges}$

$\mathrm{AdjacencyMatrix}\left(G\right)$

$\left[\begin{array}{cccc}0& 1& 0& 1\\ 1& 0& 1& 0\\ 0& 1& 0& 1\\ 1& 0& 1& 0\end{array}\right]$

$\mathrm{Neighbors}\left(G\right)$

$\left[\left[2\&comma;4\right]\&comma;\left[1\&comma;3\right]\&comma;\left[2\&comma;4\right]\&comma;\left[1\&comma;3\right]\right]$

$H≔\mathrm{Digraph}\left(\left[1\&comma;2\&comma;3\&comma;4\right]\&comma;\mathrm{Trail}\left(1\&comma;2\&comma;3\&comma;4\&comma;1\right)\right)$

$H≔\mathrm{Graph\; 2:\; a\; directed\; graph\; with\; 4\; vertices\; and\; 4\; arcs}$

$\mathrm{AdjacencyMatrix}\left(H\right)$

$\left[\begin{array}{cccc}0& 1& 0& 0\\ 0& 0& 1& 0\\ 0& 0& 0& 1\\ 1& 0& 0& 0\end{array}\right]$

$\mathrm{Departures}\left(H\right)$

$\left[\left[2\right]\&comma;\left[3\right]\&comma;\left[4\right]\&comma;\left[1\right]\right]$

The GraphTheory[AdjacencyMatrix] command was updated in Maple 2021.

The L parameter was introduced in Maple 2021.

The datatype, order, shape and storage options were introduced in Maple 2021.

For more information on Maple 2021 changes, see Updates in Maple 2021 .