Page 52 - ExtendSim User Guide
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Building a Model
Building the model
1) Opentherelevantlibraries,ifnecessary.(MostExtendSimlibrariesareautomatically opened when you launch ExtendSim.)
2) Addtheblockstothemodel.
3) Movethemtothedesiredpositions.
4) Addconnectionsbetweenblocks.
About libraries
Blocks used in a model are stored in repositories called libraries. The entire definition for a block (its program, icon, dialog, and so on) is stored in the library. When you include a block in a model, the block itself is not copied to the model. Instead, a reference to the block is included in and stored with the model. Any data you enter in the block’s dialog is also stored within the model.
There are many advantages to this method of using references to libraries instead of actual blocks in models. If you change the definition of a block in a library, all models that use that block are automatically updated. Also, block definitions are quite large, so storing just a refer- ence to the library saves memory and reduces processing time.
☞ When you save a model, ExtendSim saves the names of the blocks as well as the locations of the libraries that store the blocks. The next time you open the model, ExtendSim automatically opens the libraries the model uses. You can also set a preference in the Options window to have up to seven libraries load automatically whenever ExtendSim is launched (see“Options” on page 814).
Opening the relevant libraries
To add a block to a model, the library in which that block resides must be open. By default, the major libraries that are shipped with ExtendSim automatically open when you launch the application. The instruction below are for situations where you have closed a library or when you want to open a custom library.
The Reservoir model needs blocks from the Value and Plotter libraries. If those libraries aren’t already open:
Choose Library > Open Library. ExtendSim takes you to the Libraries folder. Select the Value library.
Click Open.
Repeat the above steps to open the Plotter library.
Open libraries are listed in alphabetical order at the bottom of the Library menu.
Adding blocks to the model
There are two main methods for adding a new block to a model:
• Select the block from its library within the Library menu.
• DragtheblockfromaLibrarywindow,asdiscussedon“LibraryWindowmode”on page 793.

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