OpenSolver for Google Sheets currently down for new users

12 Feb 2020: It was raised to us that OpenSolver for GoogleSheets is still unaccessible to new users. We are now able to replicate this bug. From our tests, new user accounts are able to install OpenSolver for Google Sheets as an Add-on from Chrome Web Store. However, the “Sign in with Google is temporarily disabled for this app” screen will still show up when trying to open the sidebar from the ribbon. We are very sorry for the inconvenience and we have contacted Google regarding this issue. We need to wait for Google’s response on this, therefore we are unsure of when this problem will be fixed.

10 Feb 2020: This is no longer the case! OpenSolver for Google Sheets is now back online for new user installations. The “app isn’t verified” screen will no longer show up for new installations. We have also updated our privacy policy to align with Google’s requirements. For more information on the usage of Google OAuth scopes please visit our OpenSolver for Google Sheets page and our Privacy Policy page.

Original post: Changes made by Google mean that OpenSolver for Googlesheets is currently not working for new users who want to add it to their Googlesheets. (Apparently the first 100 users each month can sign in, but then further sign ins are blocked by Google.) We are working on fixing this, But we don’t know how long it will take, sorry. We suggest you use OpenSolver for Excel until we get it working properly for Googlesheets.

Sorry for the inconvenience.

Cheers,

Andrew

OpenSolver for Ecological Conservation

We justc ame across an interesting article using OpenSolver to help develop optimal policies for conservation.

https://esajournals.onlinelibrary.wiley.com/doi/full/10.1002/ecs2.2596

Commonalities in stream connectivity restoration alternatives: an attempt to simplify barrier removal optimization

Ryan A. McManamayJoshuah S. PerkinHenriette I. Jager First published: 07 February 2019 https://doi.org/10.1002/ecs2.2596

https://esajournals.onlinelibrary.wiley.com/doi/full/10.1002/ecs2.2596

Ecosphere banner


250k milestone

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.

Andrew

Fantasy Football – from OpenSolver to Cloud optimiser

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.

Cool OpenSolver Applications

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:

Andrew

Supporting OR in Developing Countries

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.

Support for dynamic named ranges

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.