Pick and drag new initial point in the viewer window. This modifies the initial x and y values. Initial values of higher derivative of y can be modified inside the text field Initial y.

Pick and drag new initial point in the viewer window. This modifies the initial x and y values. Initial values of higher derivative of y can be modified inside the text field Initial y.

Type a new differential equation. Whenever you type in a text field press enter to submit your changes. Use keyboard key i to switch back to mode allowing picking of initial values:

i	pick initial x and y values

The integrator is a fourth-order Runge-Kutta method with constant step size.

Simple ODE Demo

Controls in ODE project panel:

ODE text field	Type a new ordinary differential equation. Higher derivatives of y must be denoted dy, d2y or d3y. In this text field you can use all mathematical functions shown in list of function expressions.
Text field "Order"	Defines the order (highest derivative of y) of the differential equation
Slider "Step Size"	Discretization for x-values
Slider "Length"	Length of the x-interval to evaluate the differential equation.
Slider "Initial x"	Minimum value for x-interval
Text fields "Initial y"	The first text field shows the initial y-value, the second text field shows the initial value of the first derivative of y, if "Order" is greater than 2, further text fields for the higher derivatives are displayed.