Page 645 - ExtendSim User Guide
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Hierarchical blocks
There are two ways to create a hierarchical block:
1) Selectandencapsulateagroupofblocksintoanewhierarchical block. This is most often used to organize the complexity of an existing model and is discussed at “Making a selection into a hier- archical block” on page 621.
2) Createanewhierarchicalblockfromscratchandbuildasubmodel within it. This is used for top-down modeling as discussed in “Building a new hierarchical block” on page 621.
Presentation 619
Hierarchy
Hierarchical block adds water sources together
In a model, a hierarchical block is represented by its own icon. By default the icon is a rounded rectangle with a border, but you can use drawing tools or paste in a picture to replace the icon. To help identify them in a model, hier- archical blocks can have drop shadows, as determined by a setting in the command Edit > Options > Model tab.
You open a hierarchical block by double-clicking it. Instead of seeing a dialog inside, you see the blocks that make up the submodel. The blocks are laid out like a model, with connections, labels, and so on. Depend- ing on how the hierarchical block was created, it might also contain text, pictures, or cloned dialog items that control the blocks within the hierarchical block.
Hierarchical block default icon
The title of the hierarchical block window shows the
name of the top level model in angle brackets. The sub-
model’s connections with the rest of the model are
shown as connection text boxes (named connections
with red borders around them). In the example to the right, WaterOut is one of the outputs of the hierarchical block Water Sources.
Hierarchical blocks have two kinds of windows:
• Thesubmodelwindow.Thisiswhatisdisplayedifyoudouble-clickahierarchicalblock. Use this window to add blocks to the submodel, adjust block and connection line position- ing, rename connection text boxes, or add text and graphics to the submodel.
• Thestructurewindow.Thisisdisplayedifyoucreateanewhierarchicalblockbygivingthe command Model > New Hierarchical Block or if you select an existing hierarchical block and give the command Model > Open Hierarchical Block Structure. The structure window contains another view of the submodel pane and additional panes for modifying the hierar- chical block’s icon, adding Help, and so forth. It is shown on page 622.
Characteristics of hierarchical blocks
Hierarchical blocks are unique; they have some characteristics of a block and some character- istics of a model worksheet. All hierarchical blocks have the following in common:
• Ahierarchicalblockcancontainnoblocks,oneblock,agroupofblocks,andotherhierar- chical blocks. It can also contain text, graphics, cloned dialog items, and pictures.
Hierarchical block open
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