DDF

Differential Direction Field. A windows forms app for estimating solutions to first order differential equations.

This app allows you to input a differential equation and an initial value so a particular solution can be determined. It will then calculate a specified number of estimates and plot them on a graph.

Installation

If you want to clone/download this repository and run the code yourself:
The code relies on the nuget packages OxyPlot.WindowsForms and MathParser.org-mXparser. You may need to install these packages manually.

For a prebuilt version, head over to the releases page to get the latest .exe.

Usage

Put your differential equation into the input box on the left. Just to be annoying, it requires dx/dt instead of dy/dx. Choose an initial value so the program can get the specific solution. The step size is the distance between points. A smaller step size will produce a more accurate graph. You can also choose the number of points to estimate - a large number of points may take some time. In the example above, I've put dx/dt = x as the differential equation. With a starting value of (0, 1), we can see (from looking at the estimate) that the solution curve looks like an exponential. Note that this is just an example. dx/dt = x is simple to solve (we know that the solution curve is x=e^t), so we don't need to use this program. It is intended for more complicated equations that do not have explicit solutions.