20 May

SolverStudio 0.09.03 (20160520) released

We have released SolverStudio_00_09_03_00 20160520. This includes:

  • Fixes for NEOS to avoid connection aborted errors (caused by NEOS getting tougher, and us having been pinging their server too frequently).
  • Update of CMPL to v1.1, which gives substantial speed improvements. (Thanks, Mike, for this.) This improves support for Mike’s CMPL/SolverStudio textbook.
  • Update to GLPK/GMPL 4.6

SolverStudio_00_09_03_00 20160520.zip (15253 downloads) 23 MB

17 Nov

SolverStudio 0.09.01 20150813 d – minor update

SolverStudio_00_09_01_00 20150813d has been released. This contains an IronPython patch to work around an IronPython 2.7.4 and 2.7.5 bug. This bug causes the error “SystemError: Handle is not initialized” in “_weakrefset.py”, line 73, within __contains__().
For more information, see https://mail.python.org/pipermail/ironpython-users/2015-April/017448.html and https://github.com/IronLanguages/main/issues/1187
Many thanks to SolverStudio user Andres Sommerhoff for following this up and suggesting this patch.

If you have not encountered this error, then there is no advantage in upgrading.

SolverStudio_00_09_01_00 20150813d.zip (6711 downloads) 32 MB

Note: The download file is named “SolverStudio_00_09_01_00 20150813d.zip”, with the “d” indicating the change to the IronPython “_weakrefset.py” file.

03 Sep

SolverStudio 0.09.01 (20150813) now with MOSEK examples

We have just (on 20150903) updated the latest SolverStudio download to the following file:

SolverStudio_00_09_01_00 20150813c.zip (10155 downloads) 32 MB

This is still the same underlying SolverStudio 09.01 release, but the download now includes a new example spreadsheet showing how the MOSEK solver can be used from SolverStudio. More information is available on the MOSEK language page.

Many thanks to Andrea Cassioli from MOSEK for working with us to explore how best to integrate MOSEK with SolverStudio, and creating the new examples and information page.

17 Aug

SolverStudio 0.09.01 (20150813) released

We have just released a new version of SolverStudio:

SolverStudio_00_09_01_00 20150813b.zip (16523 downloads) 32 MB

This fixes issues with SolverStudio & GAMS on 64 bit systems through a significant update to the handling GDX files (thanks Eduardo), and includes fixes for display and import of  these files. We have also added a VBA example showing how to run a SolverStudio model using VBA calls, updated PuLP to v1.6.0, and fixed an AMPL data import bug. The Advanced Installers folder now contains batch files for enabling and disabling VSTO error reporting (which can be useful when debugging installation problems). All feedback welcome.

Note: The download file is named “SolverStudio_00_09_01_00 20150813b.zip”, with the “b” being a revised version in which an unused PuLP directory has been deleted, thereby making the download smaller (but having no other effect).

03 Aug

SolverStudio 0.08.02 (20150803) released

We have released SolverStudio_00_08_02_00 20150803:

SolverStudio_00_08_02_00 20150803.zip (1943 downloads) 33 MB

This includes bug fixes for CMPL/pyCMPL, and for Julia (including handling of data items containing booleans & strings, which failed in previous versions). Thanks to Mike Steglich for the CMPL fixes, and for Leonardo for reporting the Julia issues.

This is our first version compiled with Visual Studio 2013. This still targets .Net 4, but requires a newer version of the Windows installer (which most machines should have). Thanks to changes made by Microsoft, this should fix the problem when installing on machines with .Net 4 only (and no more recent version) with manifest reading errors.

29 Aug

SolverStudio 0.6.03 (20140829) released

SolverStudio 0.6.03 (20140829) has now been released, and is the recommended download. This fixes the issues reported by users in the experimental SolverStudio 0.6.0 (2014.04.07) and includes minor improvements including better searching for GAMS/AMPL/Gurobi installations, a new version of GLPK/GMPL, a fix that caused problems for non-English users, and a change that removes a Python error being reported. All feedback welcome. Andrew

16 Apr

SolverStudio 0.6.0 (2014.04.07) – Excel 2013 support, plus more

SolverStudio 0.6.0 (2014.04.07) has been released, with numerous bug fixes and improvements. This experimental beta includes:
  • beta Excel 2013 compatibility – please let us know how it works for you
  • fixes for NEOS changes,
  • the latest CBC and IPOPT solvers,
  • the latest GMPL,
  • much easier CPython support for scripting Excel,
  • a new Scintilla editor with syntax highlighting,
  • and numerous small improvements,

We have also include a new example file, “Common Formulations.xlsx”, that makes it easy to solve common optimisation models, including transportation, transshipment, assignment and knapsack model. You can also enter and solve a standard (inter) linear program, and should be able to solve more quickly than you can using OpenSolver. None of these require any understanding of SolverStudio models, and so are suitable for a wider range of users.

The new editor (and thus SolverStudio) needs the full .Net Framework 4.0, and not the .NET Framework 4 Client Profile as was used previously. This will be installed if required, and may require administrator privileges.
All feedback most welcome.
25 Jun

SolverStudio_00_50_40 (2013.06.25): Bug fixes and Improvements

This latest version of SolverStudio (SolverStudio_00_50_40 2013.06.25) has many bugs fixes and improvements. Many thanks go to Ted Ralphs for testing SolverStudio in his classes; he has uncovered lots of issues and encouraged us to make numerous improvements. Daniel Frances has also made valuable contributions to this release by encouraging us to provide an installer suitable for use in a lab where SolverStudio must be available to all users.

The (almost) full list of fixes and changes is given in the extract below from ChangeLog.txt. This covers 3 releases, only the last of which was a public release.
Package version 0.5.4 (2013.06.25),
1/ Added beta support for all-user installations on 32 and 64 bit Windows
2/ Added support for suffixes in AMPL (and AMPL on NEOS), so naming a data item rhs.dual will allow an AMPL statement like “display rhs.dual > Sheet;” to show the dual variable values on the sheet. (Previously, dots in data item names were banned.) Thanks to Ted Ralphs for requesting this.
3/ Added an AMPL menu to allow the user to choose the SolverStudio AMPL installation, meaning solvers and AMPL.exe are used from the downloaded student version of AMPL. If this is not chosen, any AMPL and any solvers found on the machine will be used (which will typically use up licenses from a license server.)
4/ Added a work around for Pyomo to write data as AMPL tables, not lists, thereby by-passing a Pyomo limitation. (This limitation is being fixed by the Pyomo team. Thanks go to Ted Ralphs for pointing this out.)
5/ Added a new File menu item to view the SolverStudio XML data added to the spreadsheet; this is most useful for debugging.
6/ Fixed a bug where hidden rows/columns caused a crash when displaying data items
7/ Changed the code to update the internal data within the spreadsheet (including the model text and settings) on each change if it has not been updated in the last 30s. This means model changes will be saved as part of Excel’s Auto Save functionality, with less being lost if Excel crashes. (Previously, the internal spreadsheet structures were only updated before a user save.) Thanks, Ted Ralphs, for pointing this out.
8/ Updated to PuLP 1.5.4 (with a minor tweak by AJM)
9/ Updated to GMPL GLPK 4.51
10/ Added a new SolverStudio.UpdateDataItemsOnSheet() method that Python models can use to push changes in data items back onto the sheet during the running of a Python model.
11/ Fixed the data items display to work with hidden rows and columns
12/ Update examples to include an AMPL suffix example
13/ Improved the centering of the install AMPL dialog
14/ Added a File … View Examples menu

SolverStudio Package 0.5.2 (2013.06.03) (prvivte release)
2/ Updated the AMPL, GMPL and AMPL on NEOS Python code to all close the ‘sheet’ file after processing it; it was previously being left open
3/ Changed SolverStudio C# code to version SolverStudio_00_05_20 (2013.06.03) to:
3A/ Fix a serious bug where enabling VBA code in a sheet resulted in the model/sheet connection being broken, causing random models to show up as the active sheet was changed. This only happened when the user “enabled” the VBA code after first loading the sheet, which caused Excel to apparently open a new workbook (while actually re-opening the old one, and hence confusing SolverStudio).
3B/ Create (and then delete) temp working directories with randomised names, thsu allowing multiple SolverStudio’s to run at the same time on the same PC. Code is also more efficient now in that it remembers the folder name once it has been created
3B/ Support “all users” installations by reading registry keys from HK_Local_Machine as well as HK_Current_User
3C/ Added in more debug output as part of fixing 3A
4/ Updated colours in Data Items editor dialog (now version 0.52 beta) to be more standard (and look better on newer Windows)
5/ Added work-around to COOPR/Pyomo code to handle Pyomo’s errors reading is data files containing simple indexed lists (thanks to Ted Ralphs’ error report)
6/ CHanged AMPL and AMPLonNEOS to output numeric data items using “g” format, meaning integer values end up as integers (eg 5, and not 5.0) within AMPL sets and indices
7/ Changed Pyomo Solver list to be anything found in Solvers folder, plus a bunch of standard solvers (which are not checked for being installed)
8/ Solver check for existance in AMPL is currently disabled
9/ Upgraded to a new CBC with AMPL support (thanks Victor from AMPL).
10/ Added support for data items with suffixes, eg var.rc, as need in AMPL (and AMPL on NEOS) to get duals, reduced costs etc. This ishandled via “escaping” of data item names. Itis not yet implemented out AMPL and AMPLonNEOS
11/ Improved the uninstall code in About SolverStudio to uninstall both current and all-users, and forcibly remove registry entries if the current-user uninstall fails.
12/ Added a new Use SolverStudio’s AMPL Student Version menu which will use the AMPL+Solvers installed using the Install AMPL Student Version, even if there is another AMPL+solvers installed.
13/ Fixed a bug in the modified COOPR code where quotes were missing around strings with spaces in them

SolverStudio_00_05_01_00 (2013.03.27) (private release)
1/ Changed the Data Items editor to fix problems where some data items were not being correctly displayed after edits
2/ Fixed a problem runnig Gurobi when SolverStudio was installed in a directory containing spaces
3/ Introduced a ‘package version’ as distinct to the C# code version which is now reported in the About SolverStudio.
4/ Centered the Gurobi licesing output dialog