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- back [int] Set by Depth-first search for each vertex v, this
attribute stores the discovery time of the
earliest ancestor which v is adjacent to via
a back edge.
- color [char *] This attribute, commonly associated with both
vertices and edges, takes on string values
representing Tk colors. See the Tk manual
for details, but the values are typically
very straightforward, e.g. "blue" or "green."
The STk interface uses this value to determine
the actual color of each vertex or edge (and can
modify it).
- direction [int] This outdated attribute stores information
indicating whether an edge object is directed
or undirected. A more natural way to tell this
is: e->vertices()->sortedQ(), where an
answer of ``yes'' means undirected.
- distance [double] Distance calculations such as shortest paths
use and modify this attribute, usually associated
with vertices.
- name [char *] This attribute stores the name by which this graph
or graph object is identified. This attribute
should never change.
- finishtime [int] Depth-first search sets this attribute
as it finishes searching the neighbors of
each vertex. Ordering the vertices by
finishtime yields a postorder walk.
- label [char *] The label of a vertex or edge is a
string of text currently associated with
the object. Users and algorithms may
change this from the interface and from
C++ programs.
- low [int] Set by Depth-first search for each vertex v, this
attribute stores the discovery time of the
earliest proper ancestor to which any child of
v is adjacent to via a back edge.
- mark [int] This general purpose attribute is provided
to call attention to special vertices or
edges. For example, the strongly connected
components algorithm sets this mark for each
component leader.
- partition [int] Various graph algorithms partition the
vertex and/or edge sets of a graph into two
or more parts. This attribute is used to
store the locations of graph objects.
- pred [Vertex*] Graph searches induce a tree which is very
useful for constructing more advanced
algorithms. This tree is stored in the
form of predecessor information for
each vertex. The root of the search tree is
found by following pred
pointers as far as possible.
- size [int] This attribute is usually associated only
with Vertex objects, and specifies the
size in pixels of the vertex on the screen.
- starttime [int] Depth-first search sets this attribute
as it discovers
each vertex. Ordering the vertices by
starttime yields a preorder walk.
- type [int] This is another general purpose attribute.
One examples usage is to store the
classification of an edge e during and
after a depth-first search.
- width [int] The width of an edge is the screen
width in pixels. Common values range from
1 to 4.
- weight [double] Graphs with vertex and edge weights arise
in many, many applications. This double-
precision attribute stores the weight of
a Vertex or Edge object.
- x [double] This is the ``x'' coordinate of a Vertex
object
or the label (and control point) of an
Edge object. The value is expected to
be in world coordinates, where the world
ranges from 0 to 1 in each direction.
- y [double] Similar to ``x.''
Next: Building Graphs
Up: Algorithms
Previous: ContainerNode
RHS Linux User
1/26/1998