SUGARSCAPE

Python implementation of the Sugarscape agent-based computational model introduced in Growing Artificial Societies (1996) by Epstein and Axtell.

Inspired by previous work from Herve Lange (https://github.com/langerv/sugarscape) and Joshua Palicka (https://github.com/joshuapalicka/sugarscape).

Requirements:
Python 3

Usage:
python sugarscape.py

Makefile Options:
make clean
    Clean up working files and logs created by the software.
    Note: will remove any JSON files created by the other make options.
make data
    Run 20 random seeds comparing Bentham's utility calculus to the baseline greedy decisionmaking.
    Note: results will be saved in the data subdirectory.
make plots
    Generate data plots from any JSON files in the data subdirectory.
    Note: plots are dependent on a dataset existing and will create it if necessary.
make test
    Run the simulation using the default config.json file and storing a local log in the log.json file.

Preconfigured Examples from Growing Artificial Societies:
A selection of examples can be found in the examples directory.
Each demonstrates a concept from the book Growing Artificial Societies.
Examples are included to demonstrate adherence to or deviation from the source material.

immediate_growback.json:
    Agent sugar collection with immediate sugar growback (pgs. 21-26).

constant_growback.json:
    Agent sugar collection with constant sugar growback (pgs. 28-30).

agent_replacement.json:
    Agent replacement with constant sugar growback (pgs. 32-33).

seasonal_migration.json:
    Agent migration with seasonal sugar growback (pgs. 43-45).

pollution_formation.json:
    Agent sugar collection with constant sugar growback and pollution (pgs. 45-50).

reproduction_basic.json:
    Agent reproduction with constant sugar growback (pgs. 55-58).

reproduction_limited.json:
    Agent reproduction with lower infertility age, lower reproduction cost, and constant sugar growback (pgs. 64-66).

reproduction_inheritance.json:
    Agent reproduction with child wealth inheritance and constant sugar growback (pgs. 67-68).

cultural_tagging.json
    Agent cultural tagging with constant sugar growback (pgs. 72-79).

combat_unlimited.json:
    Agent combat with unlimited combat loot and constant sugar growback (pgs. 82-83).

combat_limited.json:
    Agent combat with unlimited combat loot and constant sugar growback (pgs. 86-90).

spice_growback.json:
    Agent sugar and spice collection with constant sugar and spice growback (pgs. 96-99).

trade_basic.json:
    Agent sugar and spice collection with trading and constant sugar and spice growback (pgs. 101-107).

trade_replacement.json:
    Agent trading with agent replacement and constant sugar and spice growback (pgs. 120-122).

trade_pollution.json:
    Agent trading with sugar pollution and constant sugar and spice growback (pgs. 127-129).

foresight_basic.json:
    Agent sugar and spice collection with foresight consideration and constant sugar and spice growback (pgs. 129-130).

lending_basic.json:
    Agent sugar and spice collection with lending and constant sugar and spice growback (pgs. 131-133).

disease_basic.json:
    Agent sugar and spice collection with disease and constant sugar and spice growback (pgs. 141-147).

JSON Configuration File Options:
The simulation provides a default set of options in a dictionary in the sugarscape.py file.
A JSON configuration file can be passed to the simulation, overwriting the default configuration, with the --conf option.

agentAggressionFactor: [float, float]
    Set the aggressiveness of an agent.
    The more aggressive an agent the more likely they will be enticed by combat options.
    Default: [0, 0]

agentBaseInterestRate: [float, float]
    Set the interest rate for an agent's lending as a percentage.
    Default: [0.0, 0.0]

agentEthicalFactor: [float, float]
    Set the agent weight of ethical decisionmaking over biological imperatives.
    Default: [0, 0]

agentEthicalTheory: string
    Set the agent ethical theory for algorithmic decisionmaking.
    Options: "altruisticHalfLookaheadBinary", "altruisticHalfLookaheadTop", "benthamHalfLookaheadBinary", "benthamHalfLookaheadTop", "benthamNoLookaheadBinary", "benthamNoLookaheadTop", "egoisticHalfLookaheadBinary", "egoisticHalfLookaheadTop", "none"
    Default: "none"

agentFemaleInfertilityAge: [int, int]
    Set the timestep age at which female agents become infertile.
    Default: [0, 0]

agentFemaleFertilityAge: [int, int]
    Set the timestep age at which female agents become fertile.
    Default: [0, 0]

agentFertilityFactor: [float, float]
    Set the fertility bonus for the agent.
    The higher the factor, the fewer resources the agent expends to reproduce.
    Default: [0, 0]

agentImmuneSystemLength: int
    Set the length of agent immune system tags to integer length.
    Default: 0

agentInheritancePolicy: string
    Set wealth inheritance policy on agent death to given string.
    Options: "children". "daughters", "friends", "none", "sons"
    Default: "none"

agentLendingFactor: [float, float]
    Set lending aggressiveness of agent.
    The more aggressive an agent is to lend, the higher the offered interest rate will be.
    Default: [0, 0]

agentLoanDuration: [int, int]
    Set the agent's provided loan duration in timesteps.
    Default: [0, 0]

agentLookaheadFactor: [int, int]
    Set the agent's consideration of metabolic costs in timesteps ahead.
    Default: [0, 0]

agentMaleInfertilityAge: [int, int]
    Set the timestep age at which male agents become infertile.
    Default: [0, 0]

agentMaleFertilityAge: [int, int]
    Set the timestep age at which male agents become fertile.
    Default: [0, 0].

agentMaleToFemaleRatio: float
    Set the ratio of males to females in starting population as a real number.
    Default: 1.0

agentMaxAge: [int, int]
    Set maximum agent age in timesteps.
    Note: A value of -1 indicates an infinitely lived agent.
    Default: [-1, -1]

agentMaxFriends: [int, int]
    Set maximum number of friends tracked by an agent.
    Default: [0, 0]

agentMovement: [int, int]
    Set maximum movement distance per timestep for agent.
    Default: [1, 6]

agentReplacements: int
    Set maximum number of agents to replace in environment on agent death.
    Default: 0

agentSelfishnessFactor: [float, float]
    Set the agent weight of how egoistic ethical decisions are
    Note: Valid range [0.0, 1.0], use -1 to disable
    Default: [-1, -1]

agentSpiceMetabolism: [float, float]
    Set agent metabolism for spice per timestep.
    Default: [0, 0]

agentStartingSpice: [float, float]
    Set agent starting spice hold.
    Default: [0, 0]

agentStartingSugar: [float, float]
    Set agent starting sugar hold.
    Default: [10, 40]

agentStartingQuadrants: [int (,int, int, int)]
    Set quadrants agents will initially be placed.
    Quadrant 1 begins in the top left.
    Quadrant 2 begins in the top right.
    Quadrant 3 begins in the bottom right.
    Quadrant 4 begins in the bottom left.
    Default: [1, 2, 3, 4]

agentSugarMetabolism: [float, float]
    Set agent metabolism for sugar per timestep.
    Default: [1, 4]

agentTagStringLength: int
    Set agent cultural tags string length.
    Default: 0

agentTradeFactor: [float, float]
    Set agent trade aggressiveness.
    The more aggressive in trading an agent, the more resources they will attempt to trade.
    Default: [0, 0]

agentVision: [int, int]
    Set the distance in the four cardinal directions an agent can see.
    Default: [1, 6]

debugMode: [string, ...]
    Set the debug printing mode.
    Options: "agent", "all", "cell", "disease", "environment", "ethics", "none",  "sugarscape"
    Default: "none"
    Note: Some options may cause no output in current impementation.
          Can select multiple debug modes simultaneously.

diseaseAggressionPenalty: [float, float]
    Set the impact a disease will have on an agent's aggressiveness.
    Note: Negative values constitute an aggressiveness decrease.
    Default: [0, 0]

diseaseFertilityPenalty: [float, float]
    Set the impact a disease will have on an agent's fertility.
    Note: Negative values constitute a lack of fertility.
    Default: [0, 0]

diseaseMovementPenalty: [int, int]
    Set the impact a disease will have on an agent's movement distance.
    Note: Negative values constitute a decrease in movement range.
    Default: [0, 0]

diseaseSpiceMetabolismPenalty: [float, float]
    Set the impact a disease will have on an agent's spice metabolism rate.
    Note: Negative values constitute a decrease in agent metabolism.
    Default: [0, 0]

diseaseSugarMetabolismPenalty: [float, float]
    Set the impact a disease will have on an agent's sugar metabolism rate.
    Note: Negative values constitute a decrease in agent metabolism.
    Default: [0, 0]

diseaseTagStringLength: [int, int]
    Set the length of disease tags.
    The longer the length, the longer an agent will have the disease.
    Default: [0, 0]

diseaseVisionPenalty: [int, int]
    Set the impact a disease will have on an agent's vision.
    Note: Negative values constitute a decrease in agent vision.
    Default: [0, 0]

environmentHeight: int
    Set the height in cells of the Sugarscape environment.
    Default: 50

environmentMaxCombatLoot: float
    Set the maximum reward agents receive from winning combat.
    Default: 0

environmentMaxSpice: int
    Set the maximum amount of spice at any cell in the environment.
    This amount will only be present at spice peaks.
    Default: 0

environmentMaxSugar: int
    Set the maximum amount of sugar at any cell in the environment.
    This amount will only be present at sugar peaks.
    Default: 4

environmentMaxTribes: int
    Set the maximum number of tribes in the starting population.
    Default: 0

environmentPollutionDiffusionDelay: int
    Set the delay interval in timesteps when pollution is diffused across the environment.
    Default: 0

environmentSeasonalGrowbackDelay: int
    Set the delay interval in timesteps when resources are regrown when cell is in a dry season.
    Default: 0

environmentSeasonInterval: int
    Set the interval in timesteps when environment seasons change.
    Seasons change along the equator of the environment.
    Default: 0

environmentSpiceConsumptionPollutionFactor: float
    Set the amount of pollution generated by an agent consuming spice at a cell.
    Default: 0

environmentSpiceProductionPollutionFactor: float
    Set the amount of pollution generated by an agent collecting spice at a cell.
    Default: 0

environmentSpiceRegrowRate: int
    Set the amount of spice regrown across the environment per timestep.
    Each cell can only grow up to their maximum spice value.
    Default: 0

environmentSugarConsumptionPollutionFactor: float
    Set the amount of pollution generated by an agent consuming sugar at a cell.
    Default: 0

environmentSugarProductionPollutionFactor: float
    Set the amount of pollution generated by an agent collecting sugar at a cell.
    Default: 0

environmentSugarRegrowRate: int
    Set the amount of sugar regrown across the environment per timestep.
    Each cell can only grow up to their maximum sugar value.
    Default: 1

environmentWidth: int
    Set the width in cells of the Sugarscape environment.
    Default: 50

headlessMode: bool
    Set whether the GUI is enabled.
    Default: false

logfile: path
    Set the path of the log file.
    Default: ""

profileMode: bool
    Set whether performance profiling mode is enabled.
    Default: false

seed: int
    Set the seed value for the random number generator.
    Note: Value of -1 causes simulation to generate a random seed.
    Note: Reusing a seed ensures deterministic simulation outcomes.
    Default: -1

startingAgents: int
    Set the number of agents placed in the initial population.
    Default: 500

startingDiseases: int
    Set the number of diseases placed in the initial population.
    Default: 0

timesteps: int
    Set the number of timesteps the simulation runs.
    Note: Value of -1 causes simulation to run forever or until there are no more living agents.
    Default: 200

Other Configurable Parameters:
data/collect.sh:
configs (line 3): [string, ...]
    Sets the list of decision models to run.
    Default: ["benthamNoLookaheadBinary", "benthamNoLookaheadTop", "benthamHalfLookaheadBinary", "benthamHalfLookaheadTop", "egoisticHalfLookaheadTop", "egoisticHalfLookaheadBinary", "egoisticNoLookaheadTop", "egoisticNoLookaheadBinary", "rawSugarscape"]
    Note: adding a new decision model requires a matching [model].config file to be present in the data subdirectory.

n (line 10): int
    Set the number of seeds to run.
    Default: 100

N (line 12): int
    Set the number of parallel instances of the simulation to run.
    Default: 1
    Note: this number should not exceed available CPU cores.

py (line 7): path
    Sets an alias to the system Python 3 executable.
    Default: python

Makefile:
PYTHON (line 19): path
    Sets an alias to the system Python 3 executable.
    Default: python

SH (line 20): path
    Sets an alias to the system Bash executable.
    Default: bash
    Note: use of Bash is a requirement for the shell scripts to function properly.

plots/make_plots.sh:
plots (line 1): [string, ...]
    Sets the list of plots to render.
    Default: ["population.plg", "meanttl.plg", "wealth.plg", "wealth_normalized.plg", "starvation_combat.plg"]
    Note: adding a new plot requires modifying the source code of plots/parselogs.py.

py (line 4): path
    Sets an alias to the system Python 3 executable.
    Default: python

-t (line 6): int
    Sets the number of timesteps to render for the plots.
    Default: 1000