Pyomo

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- Solvers
* MIP solver interface updates to use appropriate objective names
* Added support for suffixes in GUROBI solver interface
* Improved diagnostic analysis of PH solver for the extensive form

- Usability enhancements
* Improved robustness of pyomo_install
* Fixed Pyomo installation problem when using easy_install
* Added a script to launch the PyomoAge GUI.
* LP files now are written with the true objective name
* Rework of pyomo command line to create a concise output
* Many efficiency improvements during model generation!
* Many improvements to diagnostic output and error handling
* Expressions like "model.p > 1" can now be used within generation rules

- Modeling
* Added support for generalized disjunctive programs (in pyomo.gdp)
* Constraints can now be specified in "compound" form: lb <= expr <= ub
* Significant robustness enhancements for model expressions
* Improved error handling for constraint generation

- Other
* Python 2.5 is deprecated due to performance issues
* Python versions 2.6 and 2.7 are supported
* New MS Windows installer is now available

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- Solvers
- Various fixes for Gurobi and CPLEX
- Reorganized OS services in pyomo.os

- Usability enhancements
- Improved robustness of pyomo_install
- Default install of pyomo_install from PyPI

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- Updating dependencies for Pyomo.

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- Patch fix for pyomo.colin

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- Modeling
- Concrete models are now supported
- Nonlinear modeling extensions using the AMPL NL problem format
- Add support for immutable versus mutable parameters.
- Support for SOS1 and SOS2 constraints

- Data Integration
- Can now import data from relational databases

- Solvers
- Better support for Gurobi solver
- Direct CPLEX solver interface
- Interface to ipopt and nonlinear solvers via asl (just to be clear)
- ASL solver interface can now be specified with the form
--solver=asl:PICO

- Usability enhancements
- Numerous bug fixes.
- Updated messages to provide clearer indication of modeling errors

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- A preliminary Gurobi solver interface

- Extended syntax for data command files:
'include' command to load other data command files
'import' command to load data from other sources
namespaces to next data declarations

- The pyomo_install script can install packages from Coin Bazaar

- New conversion scripts to generate LP or NL files from Pyomo models

- Solvers now extract standard suffix information

- Various fixes to PySP solvers

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