Run¶

Run model has options to solve the model and check current running status of the model.

SOLVE¶

It is to solve the selected model, it takes input from model setup and input tables and write the solution back to output tables. Based on size and complexity of the model, it can take few minutes to hours to solve the model. A user cannot SOLVE 2 models simultaneously, user must wait for completion of previous job before submitting another. While running, system shows a running GIF at the home page to let user know that a previously submitted job is running.

Field Details:

SOLVER: User may choose which solver to use to solve the network optimization problem.

CBC is open source solver, which solves the model locally on server.

CPLEX is cloud based solver on IBM Dropsolve, to use CPLEX you must have Dropsolve API key saved in model setup.

Time Limit: Time limit for the solver to terminate.

MIP Tolerance Gap: Tolerance gap for solver to terminate.

Finetune integer variable with CBC: User may check this option while using CPLEX solver. It will run a second iteration with CBC solver taking CPLEX solution as input and then tune integer variables.

User may click on settings Settings Icon

button to include/exclude certain objectives or constraints.

Field Details:

Constraint: User may enable/disable constraints from the model using this option. By default, all the constraints are enabled and if user disable any constraint, it will remain disabled for the next run until user re enable it manually.

Objective: User may also enable/disable objective from the model, by default all the objectives are enabled.

Sub meanu details:

Fine Tune: In case on integer models, solver sometimes gives near integer values in the solution. For e.g. a facility is closed but still you might see a small volume from that closed facility, in such cases user may run Fine Tune Solution which will read existing sol file and rerun optimization with rounded values for integers.

Download MPS: User may download the MPS file generated to solve on its own machine. System ask if users wants to generate a new MPS file or download an existing one. If user made any changes since last run, it makes sense to download existing MPS else regenerate a new file. Also, for integer models, system asks if user wants to formulate big-M constraints as Indicator Constraint.

Upload Solution: User may upload .sol file generated by solver, currently system supports .sol file generated by CBC/CPLEX/XPRESS/GUROBI.

Format of .sol file for each solver is given below:

CBC:
    Stopped on time - objective value 39848141.52051586
    0 C0000000               0             -0.96296315
    1 C0000001  -7.2759576e-12             -0.96296315
    2 C0000002   7.2759576e-12             -0.96296315
    3 C0000003  -3.6379788e-12             -0.96296315
    4 C0000004   7.2759576e-12             -0.96296315
    5 C0000005               0             0.010027397

CPLEX:
     <?xml version = "1.0" encoding="UTF-8" standalone="yes"?>
     <CPLEXSolution version="1.2">
     <header
       problemName="SA_Sc10_Copy.mps"
       solutionName="incumbent"
       solutionIndex="-1"
       objectiveValue="123074023.52052048"
       solutionTypeValue="3"
       solutionTypeString="primal"
       solutionStatusValue="113"
       solutionStatusString="aborted"
       solutionMethodString="mip"
       primalFeasible="1"
       dualFeasible="0"
       MIPNodes="206509"
       MIPIterations="2797867"
     writeLevel="1"/>

XPRESS:

     Problem Statistics
     Matrix Greebfield_v4_v1
     Objective OBJ

     RHS RHS
     Problem has   1202 rows and   2160 structural columns

     Solution Statistics
     Minimization performed
     Optimal solution found after      0 iterations
     Objective function value is  2610683.365

     Rows Section
        Number    Row     At      Value      Slack Value   Dual Value        RHS
      N      1  OBJ       SB   2610683.365  -2610683.365       .000000       .000000
      E      2  C0000000  SB       .000000       .000000       .000000       .000000
      E      3  C0000001  SB       .000000       .000000       .000000       .000000
      E      4  C0000002  SB       .000000       .000000       .000000       .000000
      E      5  C0000003  SB       .000000       .000000       .000000       .000000

Import Output:User may reload output from solver solution file to output tables, this option is required only when some data in output tables in corrupted or deleted.

STATUS¶

It is to check the current/last running log of the selected model, it opens a grid with timestamp and activity completed.

ABORT¶

It is to kill the current running job, please not that it will simply kill the job and not return the best solution available at that point if time.

CPLEX STATUS¶

It shows the status of current running CPLEX job (if any)

SOLVER LOG¶

It shows the current run log of CBC solver, if the solve is already completed it will show solver log of last run.

GENERATE NETWORKFLOWS¶

Once the SOLVE is completed, user can generate network paths to populate “Network Flow” table.

GREENFIELD ANALYSIS¶

Greenfield analysis aims at taking into account the customer’s geographical location and their demand volumes to find suitable geographic locations as distribution centres.

User may run greenfield analysis to calculate centre points for customer demand. User need to provide these setups additional to input data:

Aggregate Demand By: Quantity/Weight/Volume, user may select by which UOM to aggregate customer demand.

Use Existing Facility: User may enable this option to use existing facility in greenfield analysis, if user enables it, system will ask user to choose among existing facility.

No. of additional clusters: User need to specify number of greenfield location to identify in addition to existing facilities.