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\end_header |
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|
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\begin_body |
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|
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\begin_layout Chapter |
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Managing model definitions, libraries, and projects |
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\begin_inset CommandInset label |
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LatexCommand label |
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name "cha:require" |
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|
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\end_inset |
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|
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|
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\end_layout |
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|
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\begin_layout Standard |
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Most complex models are built from parts in one or more libraries. |
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In this chapter we show typical examples of how to make sure your model |
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gets the libraries it needs. |
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We then explain in more general terms the ASCEND mechanism which makes |
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this work and how you can use it to manage multiple modeling projects simultane |
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ously. |
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\end_layout |
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|
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\begin_layout Section |
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Using |
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\family typewriter |
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REQUIRE |
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\family default |
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|
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\begin_inset Index idx |
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status collapsed |
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|
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\begin_layout Plain Layout |
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REQUIRE |
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\end_layout |
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|
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\end_inset |
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|
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and |
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\family typewriter |
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PROVIDE |
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\family default |
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|
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\begin_inset Index idx |
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status collapsed |
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|
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\begin_layout Plain Layout |
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PROVIDE |
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\end_layout |
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|
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\end_inset |
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|
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|
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\end_layout |
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|
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\begin_layout Subsection |
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|
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\family typewriter |
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REQUIRE |
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\family default |
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ing |
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\family typewriter |
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system.a4l |
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\family default |
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|
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\begin_inset CommandInset label |
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LatexCommand label |
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name "ssec:require.requireSystem.a4l" |
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|
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\end_inset |
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|
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|
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\end_layout |
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|
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\begin_layout Standard |
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Suppose you are in a great hurry and want to create a simple model and solve |
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it without concern for good style, dimensional consistency, or any of the |
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other hobgoblins we preach about elsewhere. |
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You will write equations using only generic_real variables as defined in |
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|
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\family typewriter |
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system.a4l |
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\family default |
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. |
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The equations in this example do not necessarily have a solution. |
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In your ascdata (see howto1) directory you create an application model |
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definition file |
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\begin_inset Quotes eld |
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\end_inset |
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|
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|
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\family typewriter |
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myfile.a4c |
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\family default |
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" which looks like: |
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\end_layout |
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|
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\begin_layout LyX-Code |
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REQUIRE "system.a4l"; |
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\end_layout |
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|
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\begin_layout LyX-Code |
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MODEL quick_n_dirty; |
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\end_layout |
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|
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\begin_layout LyX-Code |
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x = y^2; |
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\end_layout |
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|
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\begin_layout LyX-Code |
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y = x + 2*z; |
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\end_layout |
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|
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\begin_layout LyX-Code |
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z = cos(x+y); |
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\end_layout |
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|
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\begin_layout LyX-Code |
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x,y,z IS_A generic_real; |
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\end_layout |
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|
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\begin_layout LyX-Code |
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(* homework problem 3, due May 21. |
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*) |
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\end_layout |
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|
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\begin_layout LyX-Code |
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END quick_n_dirty; |
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\end_layout |
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|
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\begin_layout Standard |
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The very first line |
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\family typewriter |
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REQUIRE "system.a4l"; |
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\family default |
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tells ASCEND to find and load a file named |
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\family typewriter |
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system.a4l |
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\family default |
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if it has not already been loaded or provided in some other way. |
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This |
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\family typewriter |
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REQUIRE |
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\family default |
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statement must come before the |
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\family typewriter |
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MODEL |
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\family default |
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which uses the |
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\family typewriter |
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generic_real |
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\family default |
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ATOM that |
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\family typewriter |
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system.a4l |
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\family default |
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defines. |
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|
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\end_layout |
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|
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\begin_layout Standard |
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The |
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\family typewriter |
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REQUIRE |
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\family default |
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statements in a file should all come at the beginning of the file before |
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any other text, including comments. |
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This makes it very easy for other users or automated tools to determine |
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which files, if any, your models require. |
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\end_layout |
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|
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\begin_layout Standard |
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On the ASCEND command line (in the Console window or xterm) or in the Script |
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window, you can then enter and execute the statement |
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\end_layout |
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|
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\begin_layout LyX-Code |
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READ FILE "myfile.a4c"; |
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\end_layout |
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|
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\begin_layout Standard |
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to cause |
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\family typewriter |
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system.a4l |
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\family default |
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and then |
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\family typewriter |
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myfile.a4c |
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\family default |
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to be loaded. |
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\end_layout |
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|
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\begin_layout Subsection |
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Chaining required files |
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\end_layout |
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|
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\begin_layout Standard |
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Notice when you read |
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\family typewriter |
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myfile.a4c |
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\family default |
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that ASCEND prints messages about the files being loaded. |
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You will see that a file |
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\family typewriter |
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basemodel.a4l |
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\family default |
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is also loaded. |
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In |
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\family typewriter |
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system.a4l |
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\family default |
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you will find at the beginning the statements |
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\end_layout |
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|
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\begin_layout Standard |
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|
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\family typewriter |
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REQUIRE "basemodel.a4l"; |
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\end_layout |
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|
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\begin_layout Standard |
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|
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\family typewriter |
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PROVIDE "system.a4l"; |
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\end_layout |
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|
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\begin_layout Standard |
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The basemodel library is loaded in turn because of the |
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\family typewriter |
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REQUIRE |
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\family default |
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statement in |
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\family typewriter |
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system.a4l |
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\family default |
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. |
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We will come back to what the |
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\family typewriter |
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PROVIDE |
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\family default |
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statement does in a moment. |
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This chaining can be many files deep. |
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To see a more complicated example, enter |
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\end_layout |
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|
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\begin_layout LyX-Code |
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|
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\family typewriter |
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READ FILE column.a4l; |
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\end_layout |
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|
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\begin_layout Standard |
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and watch the long list of files that gets loaded. |
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If you examine the first few lines of each file in the output list, you |
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will see that each file REQUIRES only the next lower level of libraries. |
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This style minimizes redundant loading messages and makes it easy to substitute |
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equivalent libraries in the nested lower levels without editing too many |
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higher level libraries. |
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The term "equivalent libraries" is defined better in the later section |
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on |
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\family typewriter |
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PROVIDE |
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\family default |
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. |
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\end_layout |
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|
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\begin_layout Subsection |
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Better application modeling practice |
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\end_layout |
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|
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\begin_layout Standard |
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\begin_inset Marginal |
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status open |
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|
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\begin_layout Plain Layout |
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never require system.a4l in an application model. |
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\end_layout |
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|
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\end_inset |
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|
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It is generally a bad idea to create a model using only |
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\family typewriter |
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generic_real |
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\family default |
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variables. |
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The normal practice is to use correct units in equations and to use dimensional |
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variables. |
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In the following file we see that this is done by requiring |
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\family typewriter |
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atoms.a4l |
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\family default |
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instead of |
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\family typewriter |
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system.a4l |
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\family default |
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and by using correct units on the coefficients in the equations. |
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|
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\end_layout |
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|
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\begin_layout Standard |
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|
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\family typewriter |
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REQUIRE "atoms.a4l"; MODEL quick_n_clean; |
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\end_layout |
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|
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\begin_layout Standard |
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|
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\family typewriter |
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x = y^2/1{PI*radian}; |
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\end_layout |
379 |
|
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\begin_layout Standard |
381 |
|
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\family typewriter |
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y = x + 2{PI*radian}*z; |
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\end_layout |
385 |
|
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\begin_layout Standard |
387 |
|
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\family typewriter |
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z = cos(x+y); |
390 |
\end_layout |
391 |
|
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\begin_layout Standard |
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|
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\family typewriter |
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x, y IS_A angle; |
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\end_layout |
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|
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\begin_layout Standard |
399 |
|
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\family typewriter |
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z IS_A dimensionless; |
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\end_layout |
403 |
|
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\begin_layout Standard |
405 |
|
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\family typewriter |
407 |
(* homework problem 3, due May 21. |
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*) |
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\end_layout |
410 |
|
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\begin_layout Standard |
412 |
|
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\family typewriter |
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END quick_n_clean; |
415 |
\end_layout |
416 |
|
417 |
\begin_layout Subsection |
418 |
Substitute libraries |
419 |
\begin_inset Index idx |
420 |
status collapsed |
421 |
|
422 |
\begin_layout Plain Layout |
423 |
substitute libraries |
424 |
\end_layout |
425 |
|
426 |
\end_inset |
427 |
|
428 |
and |
429 |
\family typewriter |
430 |
PROVIDE |
431 |
\family default |
432 |
|
433 |
\begin_inset Index idx |
434 |
status collapsed |
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|
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\begin_layout Plain Layout |
437 |
PROVIDE |
438 |
\end_layout |
439 |
|
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\end_inset |
441 |
|
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|
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\end_layout |
444 |
|
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\begin_layout Standard |
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ASCEND keeps a list of the already loaded files, as we hinted at in Section |
447 |
|
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\begin_inset CommandInset ref |
449 |
LatexCommand ref |
450 |
reference "ssec:require.requireSystem.a4l" |
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|
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\end_inset |
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|
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|
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\noun off |
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. |
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A library file should contain a |
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\family typewriter |
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\noun default |
460 |
PROVIDE |
461 |
\family default |
462 |
\noun off |
463 |
statement, as |
464 |
\family typewriter |
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\noun default |
466 |
system.a4l |
467 |
\family default |
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\noun off |
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does, telling what library it supplies. |
470 |
Normally the |
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\family typewriter |
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\noun default |
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PROVIDE |
474 |
\family default |
475 |
\noun off |
476 |
statement just repeats the file name, but this is not always the case. |
477 |
For example, see the first few lines of the file |
478 |
\family typewriter |
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\noun default |
480 |
ivpsystem.a4l |
481 |
\family default |
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\noun off |
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, which include the statement |
484 |
\end_layout |
485 |
|
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\begin_layout LyX-Code |
487 |
PROVIDE "system.a4l"; |
488 |
\end_layout |
489 |
|
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\begin_layout Standard |
491 |
indicating that |
492 |
\family typewriter |
493 |
ivpsystem.a4l |
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\family default |
495 |
is intended to be equivalent to file |
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\family typewriter |
497 |
system.a4l |
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\family default |
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while also supplying new features. |
500 |
When ivpsystem.a4l is loaded both " |
501 |
\family typewriter |
502 |
system.a4l |
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\family default |
504 |
" and " |
505 |
\family typewriter |
506 |
ivpsystem.a4l |
507 |
\family default |
508 |
" get added to the list of already loaded files. |
509 |
For one explanation of when this behavior might be desirable, see Section |
510 |
|
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\begin_inset CommandInset ref |
512 |
LatexCommand vref |
513 |
reference "ssec:require.requireSystem.a4l" |
514 |
|
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\end_inset |
516 |
|
517 |
|
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\noun off |
519 |
. |
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Another use for this behavior is when creating and testing a second library |
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to eventually replace the first one. |
522 |
\end_layout |
523 |
|
524 |
\begin_layout Standard |
525 |
When a second library provides compatible but extended definitions similar |
526 |
to a first library, the second can be substituted for the first one. |
527 |
The second library will obviously have a different file name, but there |
528 |
is no need to load the first library if we already have the second one |
529 |
loaded. |
530 |
|
531 |
\family typewriter |
532 |
ivpsystem.a4l |
533 |
\family default |
534 |
is a second library substitutable for the first library |
535 |
\family typewriter |
536 |
system.a4l |
537 |
\family default |
538 |
. |
539 |
Note that the reverse is not true: |
540 |
\family typewriter |
541 |
system.a4l |
542 |
\family default |
543 |
does not |
544 |
\end_layout |
545 |
|
546 |
\begin_layout LyX-Code |
547 |
PROVIDE "ivpsystem.a4l"; |
548 |
\end_layout |
549 |
|
550 |
\begin_layout Standard |
551 |
so system is not a valid substitute for ivpsystem. |
552 |
|
553 |
\end_layout |
554 |
|
555 |
\begin_layout Subsection |
556 |
|
557 |
\family typewriter |
558 |
REQUIRE |
559 |
\family default |
560 |
and combining modeling packages |
561 |
\begin_inset CommandInset label |
562 |
LatexCommand label |
563 |
name "ssec:require.requireCombiningPackages" |
564 |
|
565 |
\end_inset |
566 |
|
567 |
|
568 |
\end_layout |
569 |
|
570 |
\begin_layout Standard |
571 |
Model libraries frequently come in interrelated groups. |
572 |
For example, the models referred to in Ben Allan's thesis are published |
573 |
electronically as a package models/ben/ in ASCEND IV release 0.9. |
574 |
To use Ben's distillation libraries, which require rather less memory than |
575 |
the current set of more flexible models, your application model should |
576 |
have the statement |
577 |
\end_layout |
578 |
|
579 |
\begin_layout LyX-Code |
580 |
REQUIRE "ben/bencolumn.a4l"; |
581 |
\end_layout |
582 |
|
583 |
\begin_layout Standard |
584 |
at the beginning. |
585 |
\end_layout |
586 |
|
587 |
\begin_layout Standard |
588 |
Combining models from different packages may be tricky if the package authors |
589 |
have not documented them well. |
590 |
Since all packages are open source code that you can copy into your ascdata |
591 |
directory and modify to suit your needs, the process of combining libraries |
592 |
usually amounts to changing the names of the conflicting model definitions |
593 |
in your copy. |
594 |
|
595 |
\end_layout |
596 |
|
597 |
\begin_layout Standard |
598 |
Do NOT use |
599 |
\backslash |
600 |
instead of / in the package name given to a |
601 |
\family typewriter |
602 |
REQUIRE |
603 |
\family default |
604 |
statement even if you are forced to use Microsoft Windows. |
605 |
|
606 |
\end_layout |
607 |
|
608 |
\begin_layout Section |
609 |
How |
610 |
\family typewriter |
611 |
REQUIRE |
612 |
\family default |
613 |
finds the files it loads |
614 |
\end_layout |
615 |
|
616 |
\begin_layout Standard |
617 |
The file loading mechanism of |
618 |
\family typewriter |
619 |
REQUIRE |
620 |
\family default |
621 |
makes it simple to manage several independent sets of models in simultaneous |
622 |
development. |
623 |
We must explain this mechanism or the model management may seem somewhat |
624 |
confusing. |
625 |
When a statement is processed, ASCEND checks in a number of locations for |
626 |
a file with that name: ascdata, the current directory, and the |
627 |
\family typewriter |
628 |
ascend4/models |
629 |
\family default |
630 |
directory. |
631 |
We will describe how you can extend this list later. |
632 |
ASCEND also looks for model packages in each of these same locations. |
633 |
|
634 |
\end_layout |
635 |
|
636 |
\begin_layout Subsection |
637 |
ascdata |
638 |
\begin_inset Index idx |
639 |
status collapsed |
640 |
|
641 |
\begin_layout Plain Layout |
642 |
ascdata |
643 |
\end_layout |
644 |
|
645 |
\end_inset |
646 |
|
647 |
|
648 |
\end_layout |
649 |
|
650 |
\begin_layout Standard |
651 |
If your |
652 |
\family typewriter |
653 |
ascdata |
654 |
\family default |
655 |
directory exists and is readable, ASCEND looks there first for required |
656 |
files. |
657 |
Thus you can copy one of our standard libraries from the directory |
658 |
\family typewriter |
659 |
ascend4/models |
660 |
\family default |
661 |
to your |
662 |
\family typewriter |
663 |
ascdata |
664 |
\family default |
665 |
directory and modify it as you like. |
666 |
Your modification will be loaded instead of our standard library. |
667 |
The |
668 |
\family typewriter |
669 |
ascdata |
670 |
\family default |
671 |
|
672 |
\begin_inset Index idx |
673 |
status collapsed |
674 |
|
675 |
\begin_layout Plain Layout |
676 |
ascdata |
677 |
\end_layout |
678 |
|
679 |
\end_inset |
680 |
|
681 |
directory is typically put into your HOME |
682 |
\begin_inset Index idx |
683 |
status collapsed |
684 |
|
685 |
\begin_layout Plain Layout |
686 |
HOME |
687 |
\end_layout |
688 |
|
689 |
\end_inset |
690 |
|
691 |
directory (see Section |
692 |
\begin_inset space ~ |
693 |
\end_inset |
694 |
|
695 |
|
696 |
\begin_inset CommandInset ref |
697 |
LatexCommand vref |
698 |
reference "ssec:atoms.newVarType" |
699 |
|
700 |
\end_inset |
701 |
|
702 |
). |
703 |
\end_layout |
704 |
|
705 |
\begin_layout Subsection |
706 |
the current directory |
707 |
\begin_inset CommandInset label |
708 |
LatexCommand label |
709 |
name "ssec:require.currentDir" |
710 |
|
711 |
\end_inset |
712 |
|
713 |
|
714 |
\end_layout |
715 |
|
716 |
\begin_layout Standard |
717 |
The current directory is what you get if you type 'pwd' at the ASCEND Console |
718 |
or xterm prompt. |
719 |
Under Microsoft Windows, the current directory is usually some useless |
720 |
location. |
721 |
Under UNIX, the current directory is usually the directory from which you |
722 |
started ASCEND. |
723 |
\end_layout |
724 |
|
725 |
\begin_layout Subsection |
726 |
ascend4/models/ |
727 |
\end_layout |
728 |
|
729 |
\begin_layout Standard |
730 |
The standard (CMU) models and packages distributed with ASCEND are found |
731 |
in the |
732 |
\family typewriter |
733 |
ascend4/models/ |
734 |
\family default |
735 |
subdirectory where ASCEND is installed. |
736 |
This directory sits next to the directory |
737 |
\family typewriter |
738 |
ascend4/bin/ |
739 |
\family default |
740 |
where the |
741 |
\family typewriter |
742 |
ascend4 |
743 |
\family default |
744 |
or |
745 |
\family typewriter |
746 |
ascend4.exe |
747 |
\family default |
748 |
executable is located. |
749 |
\end_layout |
750 |
|
751 |
\begin_layout Subsection |
752 |
Multiple modeling projects |
753 |
\begin_inset Index idx |
754 |
status collapsed |
755 |
|
756 |
\begin_layout Plain Layout |
757 |
multiple modeling projects |
758 |
\end_layout |
759 |
|
760 |
\end_inset |
761 |
|
762 |
|
763 |
\end_layout |
764 |
|
765 |
\begin_layout Standard |
766 |
If you dislike navigating multi-level directories while working on a single |
767 |
modeling project, you can separate projects by keeping all files related |
768 |
to your current project in one directory and changing to that directory |
769 |
before starting ASCEND. |
770 |
If you have files that are required in all your projects, keep those files |
771 |
in your |
772 |
\family typewriter |
773 |
ascdata |
774 |
\family default |
775 |
directory. |
776 |
Under Windows, |
777 |
\family typewriter |
778 |
cd |
779 |
\family default |
780 |
to the directory containing the current project from the Console window |
781 |
after starting ASCEND. |
782 |
\end_layout |
783 |
|
784 |
\begin_layout Subsection |
785 |
Example: Finding |
786 |
\family typewriter |
787 |
ben/bencolumn.a4l |
788 |
\family default |
789 |
|
790 |
\begin_inset Index idx |
791 |
status collapsed |
792 |
|
793 |
\begin_layout Plain Layout |
794 |
bencolumn.a4l |
795 |
\end_layout |
796 |
|
797 |
\end_inset |
798 |
|
799 |
|
800 |
\end_layout |
801 |
|
802 |
\begin_layout Standard |
803 |
Suppose an application model requires |
804 |
\family typewriter |
805 |
bencolumn.a4l |
806 |
\family default |
807 |
from package |
808 |
\family typewriter |
809 |
ben |
810 |
\family default |
811 |
as shown in Section |
812 |
\begin_inset CommandInset ref |
813 |
LatexCommand ref |
814 |
reference "ssec:require.requireCombiningPackages" |
815 |
|
816 |
\end_inset |
817 |
|
818 |
|
819 |
\noun off |
820 |
. |
821 |
Normally ASCEND will execute this statement by searching for: |
822 |
\end_layout |
823 |
|
824 |
\begin_layout LyX-Code |
825 |
~/ascdata/ben/bencolumn.a4l |
826 |
\end_layout |
827 |
|
828 |
\begin_layout LyX-Code |
829 |
./ben/bencolumn.a4l |
830 |
\end_layout |
831 |
|
832 |
\begin_layout LyX-Code |
833 |
$ASCENDDIST/ascend4/models/ben/bencolumn.a4l |
834 |
\end_layout |
835 |
|
836 |
\begin_layout Standard |
837 |
Assuming we started ASCEND from directory |
838 |
\family typewriter |
839 |
/usr1/ballan/projects/test1 |
840 |
\family default |
841 |
under UNIX, the full names of these might be |
842 |
\end_layout |
843 |
|
844 |
\begin_layout LyX-Code |
845 |
/usr0/ballan/ascdata/ben/bencolumn.a4l |
846 |
\end_layout |
847 |
|
848 |
\begin_layout LyX-Code |
849 |
/usr1/ballan/projects/test1/ben/bencolumn.a4l |
850 |
\end_layout |
851 |
|
852 |
\begin_layout LyX-Code |
853 |
/usr/local/lib/ascend4/models/ben/bencolumn.a4l |
854 |
\end_layout |
855 |
|
856 |
\begin_layout Standard |
857 |
Assuming we started ASCEND from some shortcut on a Windows desktop, the |
858 |
full names of these locations might be |
859 |
\end_layout |
860 |
|
861 |
\begin_layout LyX-Code |
862 |
C: |
863 |
\backslash |
864 |
winnt |
865 |
\backslash |
866 |
profiles |
867 |
\backslash |
868 |
ballan |
869 |
\backslash |
870 |
ascdata |
871 |
\backslash |
872 |
ben |
873 |
\backslash |
874 |
bencolumn.a4l |
875 |
\end_layout |
876 |
|
877 |
\begin_layout LyX-Code |
878 |
C: |
879 |
\backslash |
880 |
Program Files |
881 |
\backslash |
882 |
netscape |
883 |
\backslash |
884 |
ben |
885 |
\backslash |
886 |
bencolumn.a4l |
887 |
\end_layout |
888 |
|
889 |
\begin_layout LyX-Code |
890 |
C: |
891 |
\backslash |
892 |
ASCEND |
893 |
\backslash |
894 |
ascend4 |
895 |
\backslash |
896 |
models |
897 |
\backslash |
898 |
ben |
899 |
\backslash |
900 |
bencolumn.a4l |
901 |
\end_layout |
902 |
|
903 |
\begin_layout Standard |
904 |
The first of these three which actually exists on your disk will be the |
905 |
file that is loaded. |
906 |
\end_layout |
907 |
|
908 |
\begin_layout Subsection |
909 |
How |
910 |
\family typewriter |
911 |
REQUIRE |
912 |
\family default |
913 |
handles file and definition conflicts |
914 |
\begin_inset CommandInset label |
915 |
LatexCommand label |
916 |
name "ssec:require.handleConflicts" |
917 |
|
918 |
\end_inset |
919 |
|
920 |
|
921 |
\end_layout |
922 |
|
923 |
\begin_layout Standard |
924 |
Normally you simply delete all types before loading a new or revised set |
925 |
of ASCEND models and thus you avoid most conflicts. |
926 |
When you are working with a large simulation and several smaller ones, |
927 |
you may not want to delete all the types, however. |
928 |
We decided to make |
929 |
\family typewriter |
930 |
REQUIRE |
931 |
\family default |
932 |
handle this situation and the almost inevitable redundant |
933 |
\family typewriter |
934 |
REQUIRE |
935 |
\family default |
936 |
statements that occur in the following reasonable way. |
937 |
\end_layout |
938 |
|
939 |
\begin_layout Standard |
940 |
When a file is |
941 |
\family typewriter |
942 |
REQUIRE |
943 |
\family default |
944 |
d, ASCEND first checks the list of loaded and provided files for a name |
945 |
that matches. |
946 |
If the name is found, then that file is checked to see if it has changed |
947 |
since it was loaded. |
948 |
If the file has changed, then any definition that was changed is loaded |
949 |
in the ASCEND Library and the new definition is used in building any subsequent |
950 |
ly compiled simulations. |
951 |
Old simulations remain undisturbed and are not updated to use the new definitio |
952 |
ns since there may be conflicts that cannot be automatically resolved. |
953 |
\end_layout |
954 |
|
955 |
\begin_layout Subsection |
956 |
Extending the list of searched directories |
957 |
\end_layout |
958 |
|
959 |
\begin_layout Standard |
960 |
ASCEND uses the environment variable |
961 |
\begin_inset Index idx |
962 |
status collapsed |
963 |
|
964 |
\begin_layout Plain Layout |
965 |
environment variable |
966 |
\end_layout |
967 |
|
968 |
\end_inset |
969 |
|
970 |
|
971 |
\family typewriter |
972 |
ASCENDLIBRARY |
973 |
\family default |
974 |
|
975 |
\begin_inset Index idx |
976 |
status collapsed |
977 |
|
978 |
\begin_layout Plain Layout |
979 |
ASCENDLIBRARY |
980 |
\end_layout |
981 |
|
982 |
\end_inset |
983 |
|
984 |
as the list of directory paths to search for required files. |
985 |
Normally you do not set this environment variable, and ASCEND works as |
986 |
described above. |
987 |
|
988 |
\end_layout |
989 |
|
990 |
\begin_layout Standard |
991 |
To see or change the value of |
992 |
\family typewriter |
993 |
ASCENDLIBRARY |
994 |
\family default |
995 |
that ASCEND is using, examine |
996 |
\family typewriter |
997 |
ASCENDLIBRARY |
998 |
\family default |
999 |
in the System utilities window available from the Script Tools menu. |
1000 |
Changes made to environment variables in the utilities window are NOT saved. |
1001 |
If you are clever enough to set environment variables before running ASCEND, |
1002 |
you can make it look anywhere you want to put your model files. |
1003 |
Consult your operating system guru for information on setting environment |
1004 |
variables if you do not already know how. |
1005 |
\end_layout |
1006 |
|
1007 |
\begin_layout Standard |
1008 |
|
1009 |
\end_layout |
1010 |
|
1011 |
\end_body |
1012 |
\end_document |