Operations Research Models and Methods / Computation / Mathematical Programming /
Linear/Integer Programming

Jensen LP/IP Solver

Using the Change Button, we have changed the Solver to the Jensen LP Solver. To use this solver the LP Solver add-in (mp_methods.xla) must be installed. When it is installed the LP Solver item appears on the OR_MM menu. The worksheet for appears almost identical for this solver except the model has been deleted from the range starting in cell A2. The Jensen Solver reads the data directly from the ranges on the worksheet. Of course, one should expect the same solution from both solvers, but they may be different if alternative optimum are present.

The sensitivity analysis given by the Jensen LP/IP Solver is shown below. Some columns have been widened from the original to show more decimal accuracy. In most cases Excel results have many decimals of accuracy that can be observed by widening the columns and choosing the General format to display numbers. The Jensen display differs from the Excel display in that lower and upper limits of ranges are shown rather than amounts of increase and decrease.

The student can use either the Excel Solver or the Jensen LP/IP Solver to find solutions to linear models. Both can solve problems that include integer variables. The Excel Solver is faster for larger problems and can also solve nonlinear problems. More information about the Excel Solver can be found in the Excel documentation or from the Frontline Systems web site. The Jensen Solver can provide additional information about the algorithmic process used to find optimum solutions. For more information see the LP/IP Solver page.

Two Limits

Updated 1/16/01
Operations Research Models and Methods

by Paul A. Jensen and Jon Bard, University of Texas, Copyright by the Authors