Adding node-type elements

The node-type elements are:

• the variable
• the compartment
• the event
• the ​​​​ state

as well as the elements used in population submodels. The T text box and  image element also behave as node-type elements, though no node is associated with them. The following procedure is used to add node-type elements.

1. Click on the required node symbol in the tool bar.
2. Click on the diagram canvas where you want to place the element.
3. At this point the caption is selected and you can type in your chosen caption (except for images).
4. Repeat (2) if you want to add more nodes of the same type.

Note that the button you selected on the tool bar remains depressed until you select another button (i.e. to add a different element, or to change into a different mode, such as label or move). This allows you to add quickly several elements of the same type.

There are other methods if you want to add just one element without leaving pointer mode. Any of the following will add a single element to the diagram:

• Drag from the tool bar symbol to the chosen place on the diagram.
• Right-click at the chosen place on the diagram, and in the context menu select "Create New" -> your chosen node type. The population submodel membership controls are listed in their own submenu.

However you add a node, it appears with a default caption, e.g., "comp33". Since this caption is rarely what it needs to be in the finished model, it is selected for editing when the node is added, so you can immediately type in a more appropriate one, e.g., "Bananas".

Note that it is not possible to add a node-type element to an area of your diagram that is already occupied. A warning message appears, so if this happens, simply click somewhere else where there is sufficient space, or move existing elements around to make sufficient space. You can also adjust the relative size of components in a submodel to make more room around them.

In: Contents >> Working with model diagrams