Jody Dillon comments

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                                            Jody Dillon

Use solution from previous Benders iteration to warm start solver

Thanks @manuelma The investment variables will be a tiny overhead, so not sure it's worth putting too much time into that

Use solution from previous Benders iteration to warm start solver

Fair enough :-)

Use solution from previous Benders iteration to warm start solver

Actually, what we need to do is use `set_start_value()` to set the start value of the investment variables to their fixed value. I am currently doing a run with slightly...

Use solution from previous Benders iteration to warm start solver

Nice... let's see how this works. I suspected something was wrong alright. The more complete soution would be to warmstart the investment variables to their fixed values. I will report...

Use solution from previous Benders iteration to warm start solver

So I'm running with the latest version and get this: ``` Warning: Non-integral bounds for integer variables rounded. Warning: No solution found from 1 MIP starts. Retaining values of one...

Use JuMP.fix_discrete_variables to calculate duals (fallback)

Good idea. As an aside, I see JuMP also now supports setting some solver options generally, such as `set_time_limit_sec` and maybe there are others. We could support these as generic...

Use JuMP.fix_discrete_variables to calculate duals (fallback)

Might need to test the performance on a real-sized problem

Is there a difference between using fix_in_out ratio compared to fix_out_in if the value is 1?

Don't forget that the `[min/max/fix]_ratio_[in/out]_[in/out]` also have associated `[min/max/fix]_ratio_[in/out]_[in/out]_units_on_coefficient` and in that case, it changes what side of the constraint the units_on term appears

Is there a difference between using fix_in_out ratio compared to fix_out_in if the value is 1?

@manuelma there is also a difference in the fix case as the units_on coefficient will effectively have a different sign depending on whether it is in/out or out/in

Is there a difference between using fix_in_out ratio compared to fix_out_in if the value is 1?

So to be more precise - the `fix_ratio_out_in_unit_flow` and `fix_ratio_in_out_unit_flow` are equivalent if they are both 1 _and_ `fix_units_on_coefficient_in_out` and `fix_units_on_coefficient_out_in` are both zero If `fix_units_on_coefficient_in_out` or `fix_units_on_coefficient_out_in` are non-zero,...