Getting started¶
Installation¶
The AMPL API can function as an add-on to any existing AMPL installation. If you do not yet have an AMPL installation on the computer where you will be working with the API, see our demo page or trial page to download a working version that can be installed quickly.
In order to install the Python API you just need to run
python -m pip install amplpy
Note: For Windows, Linux, and macOS, the amplpy package comes with binary
wheels for Python 2.7 and 3.x. Please make sure that you are
using the latest version of pip before installing amplpy (upgrade using
pip install pip --upgrade or python -m pip install pip --upgrade).
If a binary wheel for your platform is not available,
a C++ compiler and python development libraries will be required.
Initial test¶
To begin, open a command/terminal window and clone our GitHub repository:
git clone git@github.com:ampl/amplpy.git
To complete an initial test, run firstexample with
python amplpy/examples/firstexample.py <solver>
where optionally <solver> is the name of a solver that has been installed with AMPL.
(If a solver is not specified, AMPL’s default choice will be used.) This will solve
several small diet problems and then display the optimal amounts of the foods
from the last solution. Alternatively, you can download the examples directly from
https://github.com/ampl/amplpy/tree/master/examples.
Note that the folder containing the AMPL executable should be in the system search path.
Otherwise, the error message “AMPL could not be started” will be shown.
If the AMPL installation directory is not in the system search path,
you can add it passing a new Environment to AMPL as follows:
from amplpy import AMPL, Environment
ampl = AMPL(Environment('full path to the AMPL installation directory'))
Note that you may need to use raw strings (e.g., r’C:\ampl\ampl.mswin64’) or escape the slashes (e.g., ‘C:\\ampl\\ampl.mswin64’) if the path includes backslashes.
Development¶
Import the amplpy modude with
import amplpy
Together with your existing AMPL implementation, this will provide the full object library and access to all AMPL functions. Please make sure that the folder containing the AMPL executable is in the system search path.
Deployment¶
To deploy AMPL API applications to users who do not have their own AMPL installations,
include with your application the AMPL executable (ampl or ampl.exe), and the amplpy package.
Note that the folder containing the AMPL executable should be in the system search path.