Fix unwanted behavior of CLP when we expect to do dual simplex #202
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CLP is hinted to go for dual simplex but it may still go for primal, giving wrong results when in strong branching iteration limit is hit and primal has been done. Moreover, when doing dual simplex, dual solutions may be inaccure at iteration limit. To fix that, some options are set through Osi to make CLP behave as we expect.
cstat and rstat were initialized with tmp arrays in LPData and were occasionally overwritten during strong branching. Two fields have been added to LPData struct so that they are resized/freed similarly to other structures.
dual_simplex() Back in the years Ted changed this call to initial_lp_solve() and there must have been a reason for that, but it really seems that dual_simplex() is the correct call here, so we changed it back.
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CLP is hinted to go for dual simplex but it may still go for primal, giving wrong results when in strong branching iteration limit is hit and primal has been done. Moreover, when doing dual simplex, dual solutions may be inaccure at iteration limit. To fix that, some options are set through Osi to make CLP behave as we expect.