Recent changes:

0.14.0 - 2024-05-21

• Allow assigning values to indexed sets from a dictionary with the lists of members for every index.
• Add AMPL.get_iis() to return dictionaries with variables and constraints in IIS.
• Add AMPL.get_solution() to return a dictionary with the solution.

0.13.3 - 2024-02-20

• Fix issues with AMPL.solve(verbose=False) when the solver argument was not set.

0.13.2 - 2024-01-05

• OutputHandler: Flush standard output after every message.

0.13.1 - 2023-12-29

• Upgrade libampl to 2.3.7-20231229.
• Upgrade ampltools to 0.7.3 adding amplpy.bundle command.
• Fix issue with environment variables on Windows in a generic way.
• Add return_output and solvername_options arguments to AMPL.solve
  • You can now do ampl.solve(solver="gurobi", gurobi_options="outlev=1").

0.13.0 - 2023-12-26

• [Breaking] amplpy.modules now have priority in the PATH.
• Fix ampl_libpath issue on Windows.

Recent changes:

0.13.1 - 2023-12-29

• Upgrade libampl to 2.3.7-20231229.
• Upgrade ampltools to 0.7.3 adding amplpy.bundle command.
• Fix issue with environment variables on Windows in a generic way.
• Add return_output and solvername_options arguments to AMPL.solve
  • You can now do ampl.solve(solver="gurobi", gurobi_options="outlev=1").

0.13.0 - 2023-12-26

• [Breaking] amplpy.modules now have priority in the PATH.
• Fix ampl_libpath issue on Windows.

0.12.2 - 2023-12-11

• Upgrade libampl to 2.3.6-20231130.
• Add solver argument to AMPL.solve.

0.12.1 - 2023-09-21

• Fix Parameter.set_values with np.ndarray objects.

Changelog:

• Upgrade libampl to 2.2.0-20230825.
• Use x-ampl by default if available.
• Add properties AMPL.solve_result/AMPL.solve_result_num.
• Add arguments to AMPL.solve to specify problem name and verbosity.
• Allow passing pandas.Series to AMPL.set_data and Parameter.set_values.
• Add AMPL.snapshot, and implement AMPL.export_model/AMPL.export_data using it.
• [Breaking] Drop Python 3.5 compatibility.
• [Breaking] Deprecate direct access methods to amplpy.DataFrame. Deprecated methods are still available with _ prefix.

Changelog:

• Upgrade libampl to 2.1.2-20230618.
• Add AMPL.write, PresolveException, and InfeasibilityException.
• Improve handling of numpy types.
• Allow assigning values to sets from iterables.
• [Breaking] Drop async functionalities.
• [Breaking] DataFrame.to_pandas: start using multi-index by default.
• [Breaking] Drop Python 2.7 compatibility.
• [Breaking] Iterating over non-indexed sets now iterates over set members.

Changelog:

• Introduced amplpy.modules to simplify installation of AMPL and all solvers across all Python environments including (Google Colab, Docker Containers, Continuous Integration Tools, etc.)
• Now AMPL and all Solvers are available as Python Packages and can be installed as follows:

# Install Python API for AMPL
$ python -m pip install amplpy --upgrade

# Install solver modules (e.g., HiGHS, CBC, Gurobi)
$ python -m amplpy.modules install highs cbc gurobi

# Activate your license (e.g., free https://ampl.com/ce license)
$ python -m amplpy.modules activate <license-uuid>

# Import in Python
$ python
>>> from amplpy import AMPL
>>> ampl = AMPL() # instantiate AMPL object

[Documentation] [AMPL Modules for Python] [Available on Google Colab]

Changelog:

• Update libampl to 2.0.11-20220823.
• Ensure that times and gentimes default to disabled.

Changelog:

• Update libampl to 2.0.10-20220627.
• Disable options times and gentimes during internal operations.

Changes:

• Improved handling of numpy types

Changes:

• [BREAKING] Raise RuntimeError in Entity.get_values if there are any issues with the data.
• Update libampl to 2.0.9.20220527.
• Fixed hanging when license check fails on Windows.
• Add ampltools as dependency.
• Allow '-' in option names.
• Drop 32-bit support.

Changes:

• [BREAKING] Raise KeyError exceptions instead of TypeError when accessing entities that do not exist.