If your matrix can be reorganize as an Robinson matrix, you have a lot of good algorithms as I described in the manual of PermutMatrix, a software for seriation and clustering (http://www.lirmm.fr/~caraux/PermutMatrix/). I also give some references. For the general case, I think you have to perform every reordering if you want an exact solution. Gilles Le 18:18 29/06/2005, vous avez écrit: >Mighty mathematicians we have a question. > >We have small matrices of integers that we need to reorder so that the sum >of the diagonal is maximum. > >These matrices are relatively small (say 10x10 max) so we can brute force >our way by performing every reordering, but would rather not. > >Can anyone help we biostatisticians with an algorithm or theorem? > > >Bill >--- > > Biostatistics Consulting Center > http://ilya.wustl.edu/~shannon/bcc_announcement.pdf > > >William D. Shannon, Ph.D. > >Associate Professor of Biostatistics in Medicine >Division of General Medical Sciences and Biostatistics > >Washington University School of Medicine >Campus Box 8005, 660 S. Euclid >St. Louis, MO 63110 > >Phone: 314-454-8356 >Fax: 314-454-5113 >e-mail: [log in to unmask] >web page: http://ilya.wustl.edu/~shannon