PDEPy

A Python 3 library for solving initial and boundary value problems of some linear partial differential equations using finite-difference methods.

• Laplace
  • Implicit Central
• Parabolic
  • Explicit Central
  • Explicit Upwind
  • Implicit Central
  • Implicit Upwind
• Wave
  • Explicit
  • Implicit

Usage

Installation

pip install pdepy

Examples

Laplace's Equation

import numpy as np
from pdepy import laplace

xn, xf, yn, yf = 30, 3.0, 40, 4.0

x = np.linspace(0, xf, xn + 1)
y = np.linspace(0, yf, yn + 1)

f = lambda x, y: (x - 1) ** 2 - (y - 2) ** 2
bound_x0 = f(0, y)
bound_xf = f(xf, y)
bound_y0 = f(x, 0)
bound_yf = f(x, yf)

axis = x, y
conds = bound_x0, bound_xf, bound_y0, bound_yf

laplace.solve(axis, conds, method="ic")

Parabolic Equation

import numpy as np
from pdepy import parabolic

xn, xf, yn, yf = 40, 4.0, 50, 0.5

x = np.linspace(0, xf, xn + 1)
y = np.linspace(0, yf, yn + 1)

init = x ** 2 - 4 * x + 5
bound = 5 * np.exp(-y)

p, q, r, s = 1, 1, -3, 3

axis = x, y
conds = init, bound, bound
params = p, q, r, s

parabolic.solve(axis, params, conds, method="iu")

Wave Equation

import numpy as np
from pdepy import wave

xn, xf, yn, yf = 40, 1.0, 40, 1.0

x = np.linspace(0, xf, xn + 1)
y = np.linspace(0, yf, yn + 1)

d_init = 1
init = x * (1 - x)
bound = y * (1 - y)

axis = x, y
conds = d_init, init, bound, bound

wave.solve(axis, conds, method="i")

Development

Create virtual environment and install requirements:

bin/setup_venv

Other commands

Run command in virtual environment:

bin/run <command>

Install requirements:

bin/install_requirements

Format codebase:

bin/format

Lint codebase:

bin/lint

Run unit tests:

bin/test

Publish

Package and distribute:

bin/publish