Dworp

Flexible framework for building agent-based modeling simulations.

Requirements

• python 3
• python packages as listed in requirements.txt

Installation

Install using pip:

pip install .

To install in editable model so that changes to the framework are instantly reflected:

pip install -e .

Using

Dworp defines basic interfaces for building simulations and provides some default components to support rapid creation of agent-based models.

Agent

An agent updates its state in the step() function. The update may depend on the environment, its neighbors, past history, or other features.

An agent has two optional functions init() and complete(). The init() function is called when an agent is added to the simulation. The complete() function is called at the end of a time step.

class MyAgent(dworp.Agent):
    def step(self, new_time, env):
        # ToDo add example here
        pass

Visibility of Agent State

When agents are updating their state based on their neighbors' state, you may want to use a two stage update mechanism. In the first stage, the agents update their state privately so that their neighbors cannot see the new state. In the second stage, the agents make that state public to prepare for the next time step.

Environment

The environment captures all simulation state that does not live in the agents. This includes serving as a container for network or spatial information for determining neighbors.

Time

Time drives the simulation and implements an iterator interface. Time can be fixed in length or infinite. Time steps can be fixed in length or variable. Time can be integer or floating point.

Terminator

To stop the simulation when some condition is met, use a Terminator.

Schedule

The order that agents update and which agents update is determined by the Scheduler. Some basic schedulers are provided for round robin updates in random order or uniformly sampling.

Observer

An Observer runs after each time step. It is designed for capturing data for further processing. It has access to the agents and the environment. Multiple observers can be chained together using ChainedObserver.

Simulation

The Simulation interface defines a single realization of an agent-based simulation. Basic implementations for single stage and double stage updates are provided. Usually, you will want to inherit from one of those to define your simulation.

Logging

Each component has its own logger:

    self.logger.info("Agent {} set activity to {}".format(self.agent_id, self.activity))

The logging level can be controlled at the framework level:

    logging.getLogger('dworp').setLevel(logging.WARN)

or at the individual component level:

    logging.getLogger('dworp.agent').setLevel(logging.DEBUG)

Examples

The best way to learn the framework is by looking at the example models and their documentation.

Testing

To run the tests, use pip to install nose (pip install nose) and then in the base directory run:

nosetests

Development

The code mostly follows the PEP8 coding standard. If you are using PyCharm, it will highlight PEP8 issues. You can also manually run style checks with flake8 (pip install flake8):

flake8 dworp

The docstrings are using the Google standard.