Google has a nice article here, that includes a recommendation to use OpenSolver. Enjoy!
We justc ame across an interesting article using OpenSolver to help develop optimal policies for conservation.
Commonalities in stream connectivity restoration alternatives: an attempt to simplify barrier removal optimization
OpenSolver reached another download milestone this month. If my car had reached 300,000 on the dial, I’d be looking at getting a new one. Fortunately, OpenSolver gets better with age.
Thank to all our users for their support.
There’s a great overview of software available for optimisation in Optima (volume 103, 2017), the Mathematical Optimization Society Newsletter.
Today the download odometer rolled past another milestone:
Thanks to all our users and our development team (and most recently Jack Dunn) for supporting OpenSolver for the last 6 years. None of this would have been possible without the solvers from COIN-OR; thanks to John Forrest and Ted Ralphs for the many years of CBC development, without which the OpenSolver project would never have started.
This blog by Derek Nelson shows how he built an OpenSolver model for fantasy football that worked well for him. “My optimizer was created using Excel with the Open Solver add-in. This worked for me and the results were good. Namely, I had the highest projected points for my teams at the start of the season in both leagues I played in (the best you can hope for in the draft, in my opinion), and I ended the season by winning one league and placing second in the other.”
Derek has now gone on to create a cloud-based version of this. This work is an interesting optimisation-based project.
As this video shows, yes, OpenSolver can solve Sudoku…
A nice article here by Jangho Lee, Seoul National University, on a Statistical Approach for Clustering Member of Congress in South Korea. Jangho used Python, Excel and Gephi for visualizing.
Image from http://jangholee.org/?p=57
I recently received a nice email from Andrew Trapp, Assistant Professor, School of Business, Worcester Polytechnic Institute. Andrew has been using OpenSolver and SolverStudio in his student projects. He writes:
I’m writing to first of all thank you for the excellent software tools that you make, OpenSolver and SolverStudio, that I have been using and featuring for 4 years now in my optimization courses. They have also been used in a number of “senior design” projects that I have advised (specifically, OpenSolver in conjunction with VBA…)
Andrew’s OpenSolver projects look very interesting, and show how OpenSolver can be used in practical applications. The reports are available online, as follows:
OpenSolver and COIN-OR are pleased to be part of the IFORS initiative to support operations research activities in developing countries, where access to specialist commercial software is often prohibited by licensing costs. For more on this initiative, see the IFORS Developing Countries OR Resources Website.
A nice article on using OpenSolver for Google Sheets for FanDuel optimisation…
One of the features that we have enjoyed in SolverStudio is support for dynamic ranges, i.e. named ranges that are created using formulae. OpenSolver 2.8 and later now supports this, and so you can use formulae to define ‘dynamic’ named ranges that are then used for the left hand side and right hand side of constraints, for the decision cells and for the objective. So for example, instead of having a constraint left hand side of A1:A4, you can defined a named range Constraint1LHS with a formula such as “=offset($A$1, 0, 0, COUNTA($A:$A),1)”. This range is dynamic in that it automatically expands as more values are entered into the A column. You can then set up a constraint in which you enter Constraint1LHS for the left hand side range. This means your model automatically works as the user changes the data on the sheet. For more information on dynamic range, see excel-easy.com or ozgrid.com. We hope you find this useful.
We have just uploaded OpenSolver 2.8.2, available on our SourceForge site here.
This is a second attempt to work around the “Automation Error” bug that some users are seeing on some versions of Excel. (This appears to be caused by a VBA bug that is corrupting the cached code. We have now “cleaned” the code)
As always, please send us any feedback and let us know if you have any problems.