-------- Forwarded Message -------- From: Andrew Mason <[email protected]> To: [email protected], [email protected] Subject: GMPL Piping Feature Request (for SolverStudio integration) Date: Mon, 23 Jul 2012 14:38:24 +1200
Andrew, As an extension to my work with OpenSolver, I have been developing SolverStudio, a free Excel add-in that makes AMPL and GMPL available for building models inside Excel. (See http://solverstudio.org and http://opensolver.org for more info). I have really enjoyed working with GMPL to add it as an option in SolverStudio; it's a great system you have created. One issue I have come up against is the lack of piping in GMPL's "display" command. In AMPL, I use the following to write the AMPL solution back to the spreadsheet (via a file called 'Sheet'): # Write the solution to the sheet display Amount > Sheet; In GMPL, I cannot use ">" with display, but I can with print. This means the GMPL commands look something like the following (for a slightly different example): # Write the solution to the sheet (copying AMPL's display format) # Each item is quoted to ensure spaces in items work correctly printf "flow :=\n" >> "Sheet"; printf {i in Warehouses, j in Bars}: "'%s' '%s' '%s'\n", i, j, flow[i,j] >> "Sheet"; printf ";\n" >> "Sheet"; This makes it difficult for users (including my students) to easily switch from AMPL to GMPL. I was wondering if, when you were next making changes to the GMPL code, you could add piping to GMPL's display command. It would certainly help us, and, I'm sure, other SolverStudio and GMPL users. Thanks, Andrew -- Dr Andrew J Mason Dept of Engineering Science University of Auckland New Zealand +64 9 3737599 x87909 www.esc.auckland.ac.nz/Mason [email protected] www.OpenSolver.org: An open-source Solver-compatible LP/IP optimizer for Excel _______________________________________________ Help-glpk mailing list [email protected] https://lists.gnu.org/mailman/listinfo/help-glpk
