Changeset 967:6563019430ba in lemon-0.x for src/lemon/graph_utils.h

Timestamp:

11/08/04 16:22:39 (20 years ago)

Author:

Alpar Juttner

Branch:

default

Phase:

public

Convert:

svn:c9d7d8f5-90d6-0310-b91f-818b3a526b0e/lemon/trunk@1354

Message:

Several changes in doc.

File:

• src/lemon/graph_utils.h (modified) (1 diff)

src/lemon/graph_utils.h

@@ -90 +90 @@
     }
     return num;
+  }
+
+  /// Finds an edge between two nodes of a graph.
+
+  /// Finds an edge from node \c u to node \c v in graph \c g.
+  ///
+  /// If \c prev is \ref INVALID (this is the default value), then
+  /// it finds the first edge from \c u to \c v. Otherwise it looks for
+  /// the next edge from \c u to \c v after \c prev.
+  /// \return The found edge or \ref INVALID if there is no such an edge.
+  ///
+  /// Thus you can iterate through each edge from \c u to \c v as it follows.
+  /// \code
+  /// for(Edge e=findEdge(g,u,v);e!=INVALID;e=findEdge(g,u,v,e)) {
+  ///   ...
+  /// }
+  /// \endcode
+  /// \todo We may want to use the \ref concept::GraphBase "GraphBase"
+  /// interface here...
+  /// \bug Untested ...
+  template <typename Graph>
+  typename Graph::Edge findEdge(const Graph &g,
+                typename Graph::Node u, typename Graph::Node v,
+                typename Graph::Edge prev = INVALID) 
+  {
+    typename Graph::OutEdgeIt e(g,prev);
+    if(prev==INVALID) g.first(e,u);
+    else ++e;
+    while(e!=INVALID && g.tail(e)!=v) ++e;
+    return e;
   }