| Safe Haskell | Safe |
|---|---|
| Language | Haskell2010 |
Data.Graph.UGraph.DegreeSequence
- data DegreeSequence
- degreeSequence :: [Int] -> DegreeSequence
- getDegreeSequence :: (Hashable v, Eq v) => UGraph v e -> Maybe DegreeSequence
- isGraphicalSequence :: DegreeSequence -> Bool
- isDirectedGraphic :: DegreeSequence -> Bool
- holdsHandshakingLemma :: DegreeSequence -> Bool
- fromGraphicalSequence :: DegreeSequence -> Maybe (UGraph Int ())
Documentation
data DegreeSequence Source #
The Degree Sequence of a simple UGraph is a list of degrees of the
vertices in the graph
Use degreeSequence to construct a valid Degree Sequence
Instances
Construction
degreeSequence :: [Int] -> DegreeSequence Source #
Construct a DegreeSequence from a list of degrees. Negative degree values
get discarded
getDegreeSequence :: (Hashable v, Eq v) => UGraph v e -> Maybe DegreeSequence Source #
Get the DegreeSequence of a simple UGraph. If the graph is not simple
(see isSimple) the result is Nothing
Queries
isGraphicalSequence :: DegreeSequence -> Bool Source #
Tell if a DegreeSequence is a Graphical Sequence
A Degree Sequence is a Graphical Sequence if a corresponding UGraph for
it exists. Uses the Havel-Hakimi algorithm
isDirectedGraphic :: DegreeSequence -> Bool Source #
Tell if a DegreeSequence is a Directed Graphic
A Directed Graphic is a Degree Sequence for which a DGraph exists
TODO: Kleitman–Wang | Fulkerson–Chen–Anstee theorem algorithms
holdsHandshakingLemma :: DegreeSequence -> Bool Source #
Tell if a DegreeSequence holds the Handshaking lemma, that is, if the
number of vertices with odd degree is even
Graph generation
fromGraphicalSequence :: DegreeSequence -> Maybe (UGraph Int ()) Source #
Get the corresponding UGraph of a DegreeSequence. If the
DegreeSequence is not graphical (see isGraphicalSequence) the result is
Nothing