[Coin-discuss] Warm Starting Dual Simplex

[Lou Hafer]

Joseph,

	It's more a question of how to present the warm start information to
the solver. Simplex solvers tend to want a basic feasible solution specified
in terms of the primal variables. The solver will then decide whether to use
primal or dual simplex to begin iterations. The decision is based on whether
the basic solution is primal or dual feasible. If neither, the solver will 
invoke an algorithm to attain feasibility (for example, a primal `phase 1' to 
gain primal feasibility, or artificial bounds on variables to attain dual 
feasibility).

	Keep in mind that the COIN OSI layer is just that --- an interface
layer. You can give hints, but the underlying solver really makes the
decisions.

						Lou