Skip to main content

Scipy-based Delay Differential Equations solver

Project description

ddeint

Build Status

Scipy-based delay differential equation (DDE) solver. See the docstrings and examples for more infos.

Examples

from pylab import cos, linspace, subplots
from ddeint import ddeint


def model(Y, t):
    return -Y(t - 3 * cos(Y(t)) ** 2)


def values_before_zero(t):
    return 1


tt = linspace(0, 30, 2000)
yy = ddeint(model, values_before_zero, tt)

fig, ax = subplots(1, figsize=(4, 4))
ax.plot(tt, yy)
ax.figure.savefig("variable_delay.jpeg")

screenshot

from pylab import array, linspace, subplots
from ddeint import ddeint


def model(Y, t, d):
    x, y = Y(t)
    xd, yd = Y(t - d)
    return array([0.5 * x * (1 - yd), -0.5 * y * (1 - xd)])


g = lambda t: array([1, 2])
tt = linspace(2, 30, 20000)

fig, ax = subplots(1, figsize=(4, 4))

for d in [0, 0.2]:
    print("Computing for d=%.02f" % d)
    yy = ddeint(model, g, tt, fargs=(d,))
    # WE PLOT X AGAINST Y
    ax.plot(yy[:, 0], yy[:, 1], lw=2, label="delay = %.01f" % d)

ax.figure.savefig("lotka.jpeg")

screenshot

Licence

Public domain. Everyone is welcome to contribute !

##Installation

ddeint can be installed by unzipping the source code in one directory and using this command: ::

(sudo) python setup.py install

You can also install it directly from the Python Package Index with this command: ::

(sudo) pip install ddeint

Project details


Download files

Download the file for your platform. If you're not sure which to choose, learn more about installing packages.

Source Distribution

ddeint-0.2.tar.gz (6.6 kB view hashes)

Uploaded Source

Supported by

AWS AWS Cloud computing and Security Sponsor Datadog Datadog Monitoring Fastly Fastly CDN Google Google Download Analytics Microsoft Microsoft PSF Sponsor Pingdom Pingdom Monitoring Sentry Sentry Error logging StatusPage StatusPage Status page