An implementation of Tarj an's algorithm for symmetrically permuting a given matrix to block tmangular form is described. The discussion includes a flowchart of the algorithm, a complexity analysis, and a comparison with the earlier widely used algorithm of Sargent and Westerberg. T~ming results are presented from several experiments using the code developed by the authors.
['Iain S. Duff', 'J. K. Reid']
An Implementation of Tarjan's Algorithm for the Block Triangularization of a Matrix