If you want six variables to have values over 10, for example, you can select them all and tell Solver that they must be greater than or equal to 11. It's important to remember that you can select multiple cells for Cell Reference. So if you have three cells, you'll end up with the numbers 1, 2, and 3 (but not necessarily in that order)įinally, add the value for the constraint. But it also specifies that they must be between 1 and the number of cells. It specifies that every cell in the range that you select for Cell Reference must be a different number. Select the cell (or cells) to be constrained in the Cell Reference field, then choose an operator.ĪllDifferent is a little confusing. With the GRG Nonlinear and Evolutionary Solving methods, you should expect a “good,” but not provably optimal solution.To add a constraint, click the Add button next to the constraint list. Not quite the same as solving equations, but easier than running linear. With the Simplex LP Solving method, you can find a globally optimal solution given enough time – but you may have to settle for a solution that’s “close to optimal” found in a more reasonable amount of time. I also have used trendlines in charts to find the equation for the line of best fit. However, these constraints make the problem non-convex and much harder to solve.
The Simplex LP Solving method is designed for these problems. This is a linear programming problem it is also a convex optimization problem (since all linear functions are convex).
Although faster algorithms and faster processors can help, some non-convex or non-smooth models could take years or decades to solve to optimality on the fastest imaginable computers. Other issues, such as poor scaling, can also affect solution time and quality, but the above characteristics affect the intrinsic solvability of your model. The use of integer constraints on variables in your model.linear or nonlinear) between the objective and constraints and the decision variables Besides for finding the root of polynomial equations, the Excel Solver can solve equations containing exponential or logarithmic functions.