The nodes variable is a data structure in Matlab terminology but could 
easily  be treated as as N \times 3 array.

The links data structure could also be simplified but has two fields
links(i).nodes is a 1 \times 2 integer array with the node numbers 
corresponding to the link ends
links(i).prop  evaluates to a single character 'l' for (black) 
longerons, 'b' for (green) battens, and 'd' for (magenta) diagonals.

I'll try to get you some 'data' for a typical field plot by tomorrow 
morning.

Thanks

gene cliff

++++++++++++++ecliff@vt.edu++++++++++++++++
|  Eugene M. Cliff                                                      
        |
|  Reynolds  Professor Emeritus                                   |
|  Aerospace and Ocean Engineering                         |
|           and                                                         
                 |
|  Interdisciplinary Center for Applied Mathematics  |
|  Virginia Tech  -  Blacksburg, VA 24061-0531        |
|  Phone: (540) 231-7667  - FaX: (540) 231-7079    |
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