DFIELD8
Direction Field of a Differential Equation

DFIELD8 is a MATLAB program which interactively displays the direction field of a differential equation, by John Polking.

DFIELD8 is an interactive tool for studying single first order differential equations. When the program is executed, a setup window is opened. The user may enter the differential equation and specify a display window using the interactive controls in the Setup window.

When the Proceed button is pressed on the Setup window, the Display window is opened. At first this window displays a direction line field for the differential equation. When the mouse button is depressed in the Display window, the solution to the differential equation with that initial condition is calculated and plotted.

Licensing:

DFIELD8 is copyright (c) by John C. Polking, Rice University.

Related Data and Programs:

NMS, a FORTRAN90 library which includes the sophisticated SDRV package for solving systems of ordinary differential equations.

PPLANE8, a MATLAB program which interactively displays the phase plane of a differential equation, by John Polking.

RKF45, a FORTRAN90 library which solves a system of ODE's using a Runge-Kutta-Fehlberg method.

TEST_ODE, a FORTRAN90 library which define a set of tests for ordinary differential equation solvers.

Author:

John Polking.

Reference:

1. David Arnold, John Polking,
   Ordinary Differential Equations using Matlab,
   Second Edition,
   Prentice Hall, 1999,
   ISBN: 0130113816,
   LC: QA371.D37.P65.
2. John Polking's Home Page:
   http://www.math.rice.edu/~polking/

Source Code:

• dfield8.m, displays direction fields of an ODE dy/dt = f(y,t).

Examples and Tests:

• wiggle_function.png, the direction field and some trajectories for x' = x * cos(t).

You can go up one level to the MATLAB source codes.