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<Title>Challenge</Title>
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<h2>Boost Graph Library Challenge and To-Do Items</h2>
<ul>
<li>Dynamic graph algorithms such as described in <a
href="http://citeseer.ist.psu.edu/eppstein99dynamic.html">Dynamic Graph
Algorithms</a> and <a
href="http://citeseer.ist.psu.edu/alberts98software.html">A Software
Library of Dynamic Graph Algorithms</a>.
<li>Polish up code/docs for pending items and champion the formal
review. The pending items are:</li>
<ul>
<li><tt>container_traits.hpp</tt> (this should also include
the work Matt Austern is doing on this topic)</li>
<li>The queues and heaps: <tt>queue.hpp</tt>,
<tt>mutable_queue.hpp</tt>, <tt>fibonacci_heap.hpp</tt>.
Somehow merge implementation with Dietmer's heaps and queues.</li>
<li><tt>disjoint_sets</tt> </li>
</ul>
<li>Construct a set of planar graph algorithms.</li>
<ul>
<li> Is the graph planar?</li>
<li> "Walk around the block" and similar open and closed neighborhood
traversals. Note that edge traversals need to resolve to particular ends
and sides (see below), not just to the edge as a whole.</li>
<li> Given a point, find the nearest vertex, edge, or bounded polygon.
Again, edges are viewed as having left and right sides.</li>
<li> Given a line segment, find intersecting vertices, edges, or bounded
polygons.</li>
<li> Given a polygon, find intersecting whatever...</li>
<li> Various minimum bounding rectangle and clipping problems.</li>
<li> Construct a planar embedding of a planar graph.</li>
<li> Find a balanced separator of a graph.</li>
<li> Modify adjacency_list so that the out-edges can be ordered
according to a user defined comparison object.</li>
</ul>
<li>Rewrite the Qhull algorithm using the Boost Graph Library (this is
high difficulty challenge). Or, for a more manageable challenge,
write an interface for Qhull with the BGL. <a
href="http://www.geom.umn.edu/locate/qhull">Qhull</a> computes the
convex hull, Delaunay triangulation, Voronoi diagram, and halfspace
intersection about a point. Qhull runs in 2-d, 3-d, 4-d, and higher
dimensions. Qhull is used for collision detection, animation, plate
tectonics, 3-d modeling, robot motion planning, and other <a
href="http://www.geom.umn.edu/~bradb/qhull-news.html#use">applications</a>.
It is currently difficult to use from a C++ program.
</li>
<li>Explore the use of Algorithm Objects as an alternative to
the current approach with visitors.</li>
<li>Analyze the algorithms that do not yet have visitors, and
come up with visitor interfaces for them.</li>
<li>Add a check in the adjacency_list class to make sure
all the vertex property template arguments have kind=vertex_property_tag
and all edge property template arguments have kind=edge_property_tag.</li>
<li>Clean up the output functions in graph_utility.hpp to
use streams, and document all the utility functions. Replace
the random number stuff with calls to the boost random number generator.</li>
<li>Modularize the tests in test/graph.cpp to apply to particular
concepts. Make sure there are run-time tests for every BGL concept.</li>
<li>Write tests for the BGL algorithms. There are a few, but
more are needed. The example provide a sanity check but do not
provide full coverage.</li>
<li>Write up the examples from Knuth's <i>Stanford GraphBase</i> using
the BGL. The file <a
href="../example/miles_span.cpp"><tt>examples/miles_span.cpp</tt></a>
is a start.</li>
<li>Further testing of the <tt>subgraph</tt> class and add more
features.</li>
<li>Implement a minimum-cost maximum-flow algorithm.</li>
<li>Make the <tt>type</tt> of all (internal) property maps convertible to the <tt>const_type</tt> of the property maps.<li>
<li>Add static functions to <tt>adjacency_list</tt> to return the per-vertex, per-edge, and per-graph overhead.</li>
</ul>
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<TD nowrap>Copyright © 2000-2001</TD><TD>
<A HREF="http://www.boost.org/people/jeremy_siek.htm">Jeremy Siek</A>, Indiana University (<A HREF="mailto:jsiek@osl.iu.edu">jsiek@osl.iu.edu</A>)
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