start ( )

Start an empty environment. If the environment has already been started, this method will do nothing. If the call fails, the environment will have the same state as it had before the call to this method.

This method will also populate any parameter (ComputeServer, TokenServer, ServerPassword, etc.) specified in your gurobi.lic file. This method will also check the current working directory for a file named gurobi.env, and it will attempt to read parameter settings from this file if it exists. The file should be in PRM format (briefly, each line should contain a parameter name, followed by the desired value for that parameter). After that, it will apply all parameter changes specified by the user prior to this call. Note that this might overwrite parameters set in the license file, or in the gurobi.env file, if present.

After all these changes are performed, the code will actually activate the environment, and make it ready to work with models.

In general, you should aim to create a single Gurobi environment in your program, even if you plan to work with multiple models. Reusing one environment is much more efficient than creating and destroying multiple environments. The one exception is if you are writing a multi-threaded program, since environments are not thread safe. In this case, you will need a separate environment for each of your threads.

Example usage:

  env = Env(empty=True)
  env.setParam('ComputeServer', 'server.mydomain.com:61000')
  env.setParam('ServerPassword', 'mypassword')