Skip to content

Installing MIMOSA

MIMOSA is written in Python, can be installed using pip: 

pip install mimosa

If you don't have Python installed yet, we highly recommend to use Anaconda to install python.

Installing the optimisation engine IPOPT

Since MIMOSA is an optimisation model, an optimisation engine needs to be specified. This can be installed locally (see With IPOPT installed locally), but an easier way is to use a free cloud-based optimisation service called NEOS.

The MIMOSA runs can easily be sent to the NEOS server (https://neos-server.org) for remote optimisation. First, on their website, sign up for a free account. You can then run MIMOSA with NEOS enabled by simply providing it with the email address you used to sign up for NEOS:

from mimosa import MIMOSA, load_params

params = load_params()

model1 = MIMOSA(params)
model1.solve(use_neos=True, neos_email="your.email@email.com")
model1.save("run1")

Depending on the MIMOSA parameters chosen and on how busy the NEOS server is, running the model might take a while (typically a couple of minutes).

A faster way to run MIMOSA, and which doesn't require an internet connection, is to install the open-source optimisation engine IPOPT locally: 

conda install -c conda-forge ipopt
However, this sometimes fails on Windows. To fix it, go to https://www.coin-or.org/download/binary/Ipopt/ and download the latest win64-version. Unzip the files. A subfolder bin should contain the file ipopt.exe. The next step is to add this folder to your PATH environment: Windows > Edit the system environment variables > Environment variables... > Select "Path" and click Edit... > Click New and browse to the folder you just unzipped. Make sure to select the bin subfolder as this folder contains the file ipopt.exe.

More detailed steps on how to install IPOPT on Windows
  1. Once you've downloaded the zip file of the latest win64-version on the coin website (currently Ipopt-3.11.1-win64-intel13.1.zip), unzip this file to folder of your choice. In the unzipped folder, there should be a bin folder.
  2. The next step is to tell Windows to look for IPOPT in this bin directory. This is achieved by adding the relevant folder to the environment path of Windows. Click on Start (or press the Win key), type environment and press Enter. This should open the dialog Edit the system environment variables.
  3. Click on Environment variables, select Path and click edit.



  4. Here, you can add the folder with the IPOPT bin folder. Click on New and add the folder you unzipped IPOPT in, making sure to select the sub-folder bin:



  5. You can test if everything works by opening an Anaconda Prompt and typing ipopt. It should show something like this:



Once IPOPT is installed, MIMOSA can be ran without NEOS: 

from mimosa import MIMOSA, load_params

params = load_params()

model1 = MIMOSA(params)
model1.solve()  # No NEOS required
model1.save("run1")

Next: Running MIMOSA