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sunnyjung
Calcite | Level 5

I watched "PROC OPTMOEL: Solving Optimization Problems with Hybrid Approaches_ Rob Pratt" via youtube.

It was really helpful for me, Thank you so much.

 

I want to get a back data and SAS Code, Is it possible?

 

I am studying of Optimization to find the best location to reach everywhere easily.

 

I wait your reply.

 

3 REPLIES 3
RobPratt
SAS Super FREQ

Attached is the code for the p-median example.

sunnyjung
Calcite | Level 5

Thank you for your reply.

The AssignImpliesBuild is declared twice in 'pMedianMILP.sas'.

Could you explain?

 

RobPratt
SAS Super FREQ

The second declaration is commented out:

   /* if customer i assigned to site j, then facility must be built at j */
   con AssignImpliesBuild {i in CUSTOMERS, j in CUSTOMERS}:
      Assign[i,j] <= Build[j];
*   con AssignImpliesBuild {j in CUSTOMERS}:
      sum {i in CUSTOMERS} Assign[i,j] <= card(CUSTOMERS) * Build[j];

Both families of linear constraints enforce the logical implication that Assign[i,j] = 1 implies Build[j] = 1.  The first (disaggregated) version yields a tighter linear programming relaxation, but the second (aggregated) version yields fewer constraints.