graphs and networks Flashcards
simple graph
has no loops or multiple edges
isolated vertex
a vertex with a degree of 0
degenerate graph
no edges
connected graph
all vertices are connected, indirectly or directly
complete graph
all vertices are connected directly to every other vertex
bridge
an edge, where if removed, will cause the graph to become disconnected
sub graph
a part of a larger graph
equivalent graph (isomorphic)
a graph that looks different, but contains the same information
planar graph
a graph that can be drawn with no intersections of edges
faces
an area enclosed by edges, includes the outside of the graph
Eulers rule
v-e+f=2
walk
any continuous sequence of edges
trail
a walk with no repeated edges
path
a trail with no repeated vertices
circuit
a trail that starts and finishes at the same vertex
cycle
a circuit with no repeated vertices
Eulerian trial
follows every edge of the graph
exists if graph has 2 vertices with an odd degree
does not repeat edges
Eulerian circuit
an Eulerian trail that starts and finishes at the same vertex
exists if all vertices have an even degree
does not repeat edges
Hamiltonian path
visits every vertex of a graph
does not repeat vertices
Hamiltonian cycle
same as Hamiltonian path but starts and ends at the same vertex
does not repeat vertices
weighted graph
numbers associated to edges