The Fixed step options tab

Fixed step options

Figure 297: Run parameters - Fixed step options tab

The figure above shows the Run Parameters dialog box with the Fixed step options tab selected. The values and options that can be set are now described.

Integrator settings

Step to use

This setting is the fixed time step value used by the integrator.

Additionally, if Adams-Bashforth or Runge-Kutta are selected, you can set the Order of the integrator. You can set the order to 2, 3 or 4.

Integration method

• Euler If enabled, the explicit Euler (order 1) numerical integration method will be used.

• Adams-Bashforth If enabled, the Adams-Bashforth numerical integration method will be used.

• Runge-Kutta The Runge-Kutta numerical integration method will be used. Runge-Kutta methods of orders 2 to 4 are provided. Their stability improves as the order increases but the number of calls to the model per step also increases with order.