Changeset 1723:fb4f801dd692 in lemon-0.x for lemon/floyd_warshall.h

Timestamp:

10/14/05 12:53:51 (19 years ago)

Author:

Balazs Dezso

Branch:

default

Phase:

public

Convert:

svn:c9d7d8f5-90d6-0310-b91f-818b3a526b0e/lemon/trunk@2250

Message:

Really short description of these shortest path algorithms

File:

• lemon/floyd_warshall.h (modified) (4 diffs)

lemon/floyd_warshall.h

@@ -28 +28 @@
 #include <lemon/invalid.h>
 #include <lemon/error.h>
+#include <lemon/matrix_maps.h>
 #include <lemon/maps.h>
 
@@ -106 +107 @@
     typedef FloydWarshallDefaultOperationTraits<Value> OperationTraits;
  
-    /// \brief The type of the map that stores the last edges of the 
+    /// \brief The type of the matrix map that stores the last edges of the 
     /// shortest paths.
     /// 
-    /// The type of the map that stores the last
-    /// edges of the shortest paths.
+    /// The type of the map that stores the last edges of the shortest paths.
     /// It must be a matrix map with \c Graph::Edge value type.
     ///
-    typedef NodeMatrixMap<Graph, typename Graph::Edge> PredMap;
+    typedef DynamicMatrixMap<Graph, typename Graph::Node, 
+                             typename Graph::Edge> PredMap;
 
     /// \brief Instantiates a PredMap.
@@ -127 +128 @@
     ///
     /// The type of the map that stores the dists of the nodes.
-    /// It must meet the \ref concept::WriteMap "WriteMap" concept.
-    ///
-    typedef NodeMatrixMap<Graph, Value> DistMap;
+    /// It must meet the \ref concept::WriteMatrixMap "WriteMatrixMap" concept.
+    ///
+    typedef DynamicMatrixMap<Graph, typename Graph::Node, Value> DistMap;
 
     /// \brief Instantiates a DistMap.
@@ -149 +150 @@
   /// \ref concept::ReadMap "ReadMap", so it is easy to change it to any 
   /// kind of length.
+  ///
+  /// The algorithm solves the shortest path problem for each pairs
+  /// of node when the edges can have negative length but the graph should
+  /// not contain circle with negative sum of length. If we can assume
+  /// that all edge is non-negative in the graph then the dijkstra algorithm
+  /// should be used from each node rather and if the graph is sparse and
+  /// there are negative circles then the johson algorithm.
+  ///
+  /// The complexity of this algorithm is O(n^3 + e).
   ///
   /// The type of the length is determined by the