However with OpenSolver set to 0.1% tolerance, the model quickly returns a solution of 8,384,771, or 132% larger than the relaxed solution. For example, when I solve the continuous/relaxed model, the objective value being minimized is 3,613,245 (relatively large due to my penalty costs being added). The model isn’t behaving as I expected with regards to the “Branch and Bound Tolerance (%)” integer setting, as the returned values do not seem to be within the % tolerance of the continuous solution. The decision variables for ‘production quantity’ are constrained to integers (discrete production process). I’ve used OpenSolver to create a production scheduling/location MIP model (determine the production location for each piece of demand to minimize lead time to customer, subject to capacity constraints, with penalty costs added for exceeding capacity).Support.microsoft.com - Apply Today Remove or allow a circular reference - Office Support.I also created a simplified/small version of the model to test a similar structure to see if I could better isolate the error. Iterative references are formulas that are continuously repeated until the.Enable Iterative Calculation Excel Mac - XpCourse Remove or allow a circular reference - Office Support Save support.microsoft.com If you're using Excel for Mac , click the Excel menu , and then click Preferences > Calculation. I’m not sure why it is interpreting that objective value as a 1782 gap and less than 0.1%, as compared to the initial continuous objective value of 3.61324e+06? Any thoughts on what could be impacting the integer tolerance?Choose Tools > Options (LibreOffice > Preferences on a Mac) to open the. But later in the log shows: “Cbc0012I Integer solution of 8384771 found by RINS after 6986 iterations and 1239 nodes (31.55 seconds)”, then the next line is “Cbc0011I Exiting as integer gap of 1782 less than 1e-10 or 0.1%”. It also reflected the LP solution properly: “Continuous objective value is 3.61324e+06 –. I checked the “Last Solve Log” file, and saw that the tolerance is being set by the model properly: “ratioGap was changed from 0 to 0.001”.
Allow Iteration Calculations In Excel Code I CanOperator <=1.The binary variables all are set to 0 before I start the initialization. And I also found a way to fix it by debugging the VBA.Here’s the situation: I’m building a model which has some binary variables, and some contraints’ LHS are sums of binaries. Is there a VBA code I can insert to enable this automatically when the sheet is.First let me thank the OpenSolver team, this piece of software is awesome! We use it for consulting at SimWell Technologies (Montreal, Canada).I have found an issue with the QuickSolve initialization. The sheet is now about to go out to staff and won't function correctly if the iterative calculation isn't enabled. Any thoughts to point me in the right direction are greatly appreciated! FYI – if I try to solve this small model in Excel Solver with the same settings, it attempts to continue solving to try to find a solution within tolerance instead of quickly providing a solution that doesn’t meet tolerance (although note that it just continuously runs until I stop it since it doesn’t find an acceptable solution).Hi there, I have a spreadsheet I have created with iterative calculations in it (deliberately).(maybe not totally flexible for all models one could build with OpenSolver).After looking at the code, I'm thinking of maybe creating hidden sheets automatically to store all of the built model info into, and read it in just before QuickSolving. (I checked the model.lp file)In conclusion, I've added a line of code in function "AnalyseParameters" in the CQuickSolve Class module: Application.CalculateJust before the current constraint values are read…Let me know if you need an example where this issue occurs, I'll remove any customer-sensitive info from the model file and e-mail it to you.I'm thinking about making quicksolve "saveable", at least to adapt the code to make sure it works for our current project, when the user closes and re-opens the file. The same constraints' LHS are re-evaluated to 0 (instead of 8 just before) Therefore, the code THINKS there is a coefficient of 8 (or maybe minus 8, but it doesn't matter) for ALL parameters, while the constraint has nothing to do with the parameter (or any parameter for the matter).Next, when I QuickSolve, it cannot find a solution because several constraints are messed up. I'm guessing each binary value has probably been set to 1 at some point during model building…(and the LHS is a sum of 8 binary cells)Therefore, when reading/storing all of the original LHS values, the values stored are not right (they are 0)Then, when the code tests changing the parameter value in order to measure the impact on RHS, it recalculates the sheet. In this case, the calculated values on the RHS of the constraint are now valued 8 (instead of the original 0). However, the sheet does not get calculated once before starting the parameter analysis.![]()
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