The pyaimms Autolib
The pyaimms library enables seamless integration of Python and AIMMS. With pyaimms, you can run Python scripts and statements directly from AIMMS
Features
Simple setup with a
pyproject.toml
for dependencies and Python versionExecute Python code from AIMMS procedures using two intuitive functions
Getting Started
This example uses pyaimms to execute Python code from AIMMS procedures.
It includes:
you can download a pre-made example from the link below:
transport_optimization_pyaimms.7z
The pre-made example was setup in a way described below.
Add a pyproject File
Your project must include a
pyproject.toml
file in the directory of your AIMMS project. This file specifies the Python version and all dependencies required by your project. For example:[project] name = "your_project_name" version = "0.1.0" requires-python = "==3.13.*" dependencies = [ "aimmspy", "pytest", "colorama" ]
The requires-python field must match the Python version you want to use.
List all packages your Python code will import in the dependencies array.
That is it! Now you can run python code from AIMMS procedures.
Working with aimmspy
To prevent issues, it is highly recommended to create a singleton Python file (e.g., singleton.py). This file should define global variables for your AIMMS Project and Model, which can be imported by other Python modules.
For example:
from aimmspy.project.project import Project, Model from aimmspy.model.enums.data_return_types import DataReturnTypes project = Project( exposed_identifier_set_name="AllIdentifiers" ) my_aimms = project.get_model("model_stub.py")
The project holds the AIMMS project context.
The my_aimms variable provides access to the AIMMS model from Python.
After this, you can import the project and my_aimms variables in any Python module you create. For example:
from singleton import my_aimms def assign_my_data(): my_aimms.demand.assign({ ("Houston"):50, ("Phoenix"):60, ("Philadelphia"):40, }) my_aimms.supply.assign({ ("NewYork"):70, ("LosAngeles"):80, ("Chicago"):60 }) my_aimms.unit_transport_cost.assign({ ("NewYork", "Houston"): 5.0, ("NewYork", "Phoenix"): 6.0, ("NewYork", "Philadelphia"): 4.0, ("LosAngeles", "Houston"): 3.0, ("LosAngeles", "Phoenix"): 2.0, ("LosAngeles", "Philadelphia"): 7.0, ("Chicago", "Houston"): 4.0, ("Chicago", "Phoenix"): 5.0, ("Chicago", "Philadelphia"): 3.0, })
or if using data frames it can look like this
import pandas as pd from singleton import my_aimms warehouses_set = ["NewYork", "LosAngeles", "Chicago"] customers_set = ["Houston", "Phoenix", "Philadelphia"] demand_df = pd.DataFrame({ "c": customers_set, "demand": [50, 60, 40] }) supply_df = pd.DataFrame(data={ "w": warehouses_set, "supply": [70.0, 80.0, 60.0] }) unit_transport_cost_df = pd.DataFrame({ "c": ["Houston", "Phoenix", "Philadelphia", "Houston", "Phoenix", "Philadelphia", "Houston", "Phoenix", "Philadelphia"], "w": ["NewYork", "NewYork", "NewYork", "LosAngeles", "LosAngeles", "LosAngeles", "Chicago", "Chicago", "Chicago"], "unit_transport_cost": [5.0, 6.0, 4.0, 3.0, 2.0, 7.0, 4.0, 5.0, 3.0] }) my_aimms.demand.assign( demand_df) my_aimms.supply.assign( supply_df) my_aimms.unit_transport_cost.assign( unit_transport_cost_df)
Calling Python from AIMMS
pyaimms provides two key functions for executing Python code from AIMMS:
py::run_python_statement(<python_statement>): Executes a single Python statement (as a string).
py::run_python_script(<script_filename>): Executes a Python script file (by filename).
These functions are available in your AIMMS model after importing the pyaimms Autolib. The script path is relative to your AIMMS project directory.
Usage Examples
Below are examples of how to use pyaimms in your AIMMS procedures:
Executing a Python Statement
Use py::run_python_statement to run a single line of Python code, such as calling a function or modifying a variable.
py::run_python_statement("execute_main()");
Executing a Python Script
Use py::run_python_script to execute an entire Python script file. The script filename should be relative to your AIMMS project directory.
py::run_python_script("script_with_func.py");
py::run_python_script("global_assign.py");
Best Practices
Always ensure your
pyproject.toml
lists all dependencies your Python code will use.Use the singleton pattern to avoid re-initializing the aimmspy Project and Model instance multiple times.
Keep Python scripts and modules organized and accessible from the AIMMS project folder directory.
Notes & Troubleshooting
Python identifier access is case-sensitive. If you get an attribute error, check the identifier name in your AIMMS model.
The script path for run_python_script is always relative to your AIMMS project directory.
Multi processing will work differently because this has Python embedded in AIMMS. The result of this is that you can only use threading and multiprocessing will not work or only if configured correctly.
AIMMS projects using pyaimms cannot be closed and reopened within the IDE, because Python cannot be fully destructed and reinitialized in the same session. If you need to restart the project, close the AIMMS IDE completely and reopen it.
If you change your model for example by adding new identifiers, you need to call get_model() again to update the model in Python.