/couzinswarm

Simulating fish swarming behavior using the model by Iain Couzin et al.

Primary LanguagePythonMIT LicenseMIT

couzinswarm

Simulate fish swarming behavior with the model by Iain Couzin et al. Use with caution as I can't seem to replicate some behavior (e.g. the torus swarming).

Example

from couzinswarm import Swarm

swarm = Swarm()
r, v = swarm.simulate(1000)

Install

pip install couzinswarm

Elaborate example

import numpy as np
import matplotlib.pyplot as pl
from mpl_toolkits.mplot3d import Axes3D
from couzinswarm import Swarm

# note: the dimension of space is measure in fish length,
# such that r = 1 means a length of one fish

swarm = Swarm(
             number_of_fish=20,
             repulsion_radius=1,
             orientation_width=10,
             attraction_width=10,
             # this angle is given in radians
             # up to np.pi (not 360 degrees as in
             # the paper)
             angle_of_perception=np.pi,
             # radians per unit of time
             turning_rate=0.1,
             # fish lengths per unit of time
             speed=0.1,
             # in units of fish length
             noise_sigma=0.1,
             dt=0.1,
             # geometry of box
             box_lengths=[100,100,100],
             # boundary conditions
             reflect_at_boundary = [True, True, True],
             verbose=False,
             )



fig = pl.figure()
ax = fig.add_subplot(111, projection='3d')

N_t = 1000

t = np.arange(N_t+1)

# Note that r.shape = v.shape = ( N_fish, N_t+1, 3 )
positions, directions = swarm.simulate(N_t)
r, v = positions, directions

for i in range(swarm.number_of_fish):
    ax.plot(r[i,:,0], r[i,:,1], r[i,:,2])

pl.show()