GAMS — The Solver Manuals - Available Software

MPSWRITE
Contents
1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 395
2 An Example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 396
3 Name Generation: A Short Note . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 398
4 The Option File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 398
5 Illustrative Example Revisited . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 398
6 Using Analyze with MPSWRITE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 400
7 The GAMS/MPSWRITE Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 402
7.1 Name Generation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 402
7.2 Name Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 402
7.3 Using Files . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 403
7.4 Writing Files . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 403
8 Name Generation Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 404
9 Integrating GAMS and ANALYZE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 410
Release Notes
MPSWRITE 1.2 - February 22, 2000 - Differences from 1.1
• Enabled the use of long identifier and label (set element) names. In earlier versions, the length of identifier
and element names was limited to 10 characters.
• Added the option OBJLAST (OBJective row LAST) to place the objective row as the last/first row in
the MPS matrix. Most solution systems have MPS file readers which take the first free row (N) to be the
objective row. Previous versions of MPSWRITE placed the objective row as the last row in the matrix.
MPSWRITE 1.1 - April 15, 1999 - Differences from 1.0
• Updated the ANALYZE link to be compatible with the book by Harvey J. Greenberg, A Computer-Assisted
Analysis for Mathematical Programming Models and Solutions: A User’s Guide to ANALYZE, Kluwer
Academic Publishers, Boston, 1993.
• Added the option MCASE (Mixed CASE names) to control the casing of MPS names.
1 Introduction
The GAMS modeling language allows you to represent a mathematical programming model in a compact and
easily understood form and protects the user from having to represent the model in the form that is required by
any particular solver. This solver specific form is usually difficult to write and even more difficult to read and
understand. However, there may be cases in which you require the model data in precisely such a form. You may