NetworkSimplex Dead Fields

Dev
1

Hi all!
I’m currently trying to properly understand the C NetworkSimplex implementation in ns.c and have some trouble understanding some of the fields. In particular, I am wondering if (and what) the field network_simplex_ctx_t->Tree_node does. It is opulated during the subtree search, in the add_tree_edge function, however, I cannot find any later use of this. The only other read/write reference as far as i can tell is in the TB_Balance function, but there it is always overwritten from the beginning

Thanks for helping me understand this!

2

It doesn’t seem important. This list is also referenced in a debugging function tchk() (“tree check”) that was mostly helpful back when we first wrote and debugged this code.

If you can understand how the solver finds an initial feasible solution, then iteratively improves it by restructuring the “tight tree” by swapping tree edges based on cut values, you have the important details.

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