/// <inheritdoc />
public int RemoveOutEdgeIf(TVertex vertex, EdgePredicate <TVertex, TEdge> predicate)
{
if (vertex == null)
{
throw new ArgumentNullException(nameof(vertex));
}
if (predicate is null)
{
throw new ArgumentNullException(nameof(predicate));
}
IEdgeList <TVertex, TEdge> edges = _vertexEdges[vertex];
var edgesToRemove = new EdgeList <TVertex, TEdge>(edges.Count);
edgesToRemove.AddRange(edges.Where(edge => predicate(edge)));
foreach (TEdge edge in edgesToRemove)
{
edges.Remove(edge);
OnEdgeRemoved(edge);
}
EdgeCount -= edgesToRemove.Count;
return(edgesToRemove.Count);
}
/// <summary>
/// Removes the given <paramref name="vertex"/> and merges all its connection to other vertices.
/// </summary>
/// <param name="vertex">The vertex.</param>
/// <param name="edgeFactory">Factory method to create an edge.</param>
/// <exception cref="T:System.ArgumentNullException"><paramref name="vertex"/> is <see langword="null"/>.</exception>
/// <exception cref="T:System.ArgumentNullException"><paramref name="edgeFactory"/> is <see langword="null"/>.</exception>
/// <exception cref="VertexNotFoundException"><paramref name="vertex"/> is not part of the graph.</exception>
public void MergeVertex(
[NotNull] TVertex vertex,
[NotNull, InstantHandle] EdgeFactory<TVertex, TEdge> edgeFactory)
{
if (vertex == null)
throw new ArgumentNullException(nameof(vertex));
if (edgeFactory is null)
throw new ArgumentNullException(nameof(edgeFactory));
// Storing edges (not a copy)
// Remove vertex will delete some of these edges
// but it will remain needed edges to perform the merge
if (!_vertexInEdges.TryGetValue(vertex, out IEdgeList<TVertex, TEdge> inEdges))
throw new VertexNotFoundException();
IEdgeList<TVertex, TEdge> outEdges = _vertexOutEdges[vertex];
// Remove vertex
RemoveVertex(vertex);
// Add edges from each source to each target
foreach (TVertex source in inEdges.Select(source => source.Source))
{
IEnumerable<TVertex> targets = outEdges
.Where(target => !EqualityComparer<TVertex>.Default.Equals(vertex, target.Target))
.Select(target => target.Target);
foreach (TVertex target in targets)
{
// We add an new edge
AddEdgeInternal(edgeFactory(source, target));
}
}
}
/// <inheritdoc />
public int RemoveAdjacentEdgeIf(TVertex vertex, EdgePredicate <TVertex, TEdge> predicate)
{
if (vertex == null)
{
throw new ArgumentNullException(nameof(vertex));
}
IEdgeList <TVertex, TEdge> outEdges = _adjacentEdges[vertex];
var edges = new List <TEdge>(outEdges.Count);
edges.AddRange(
outEdges.Where(edge => predicate(edge)));
RemoveEdges(edges);
return(edges.Count);
}
