For a large hierarchy, you may want to view only one branch of your open hierarchy. In this case, you may wish to make your selected node the top node of the hierarchy. Your original hierarchy structure remains the same, but any nodes that are structurally above your selected node will not be visible.
To make a hierarchy component the Top Node, follow these steps:
1.Highlight the component to be made 'top node' by clicking on the text.
2.From the Main Menu (or right-click menu), select Node 
Make Top Node.
3.The hierarchy display will adjust so that the component you select will become the top node in the hierarchy display.
4.To reverse this procedure, click Expand to Top on the Node or right-click menu.
Note: When you make a component a top node, you are merely limiting your view to show just that component and its children. You are NOT unlinking it from the hierarchy.
