Parent Topic: <A href="http://www.pcigeomatics.com/cgi-bin/pcihlp/MODEL|Language">Language</a><hr>
<H4>Sections</H4>
The statements and comments which make up a model are divided up
into the following sections:
<P>
<UL>
<LI> Setup Section 
</UL>
<UL>
<LI> Equations Section 
</UL>
<UL>
<LI> Report Section 
</UL>
The `Setup' section sets up the processing environment. This
includes: prompting the user for any required data; associating
attribute data with image channels (layers); and printing messages
to the user's screen. This section is executed once before any
processing is done. The following types of statements can be
included in the `Setup' section: COMMENTS, INPUT, INPUTA, SET, SETA,
and PRINT.<p>
The `Equations' section defines the processing that should be done.
This section is applied to each pixel in the database. For example:
if the database has dimensions 512 by 512, then the equations
section would be executed 262144 times. The following types of
statements can be included in the `Equations' section: COMMENTS,
ASSIGNMENT, IF, GOTO, LABEL, and STOP. Each time this section is
applied, numeric variables are reset to the value entered from an
INPUT statement or to zero. Character variables are also reset to
values entered or to the empty (null) string.<p>
The `Report' section defines the type of report that should be
generated based on the accumulated results of the modelling
equations. This section is executed once. The following types of
statements can be included in the `Report' section: COMMENTS, TITLE,
and REPORT.<p>
When MODEL program is run, the following steps are followed.
<P>
<UL>
<LI> The model is read in and internal data structures are set up. 
</UL>
<UL>
<LI> The `Setup' section is executed and, if necessary, the user is
prompted for required data. 
</UL>
<UL>
<LI> The image database is read in and the modelling equations in the
`Equations' section are applied to each pixel. If any output
channels (layers) are generated, these are written back to the
file. 
</UL>
<PRE>
    THIS IS THE STEP WHICH TAKES ALMOST ALL THE PROCESSING TIME.
</PRE>
<UL>
<LI> Once all processing is completed, the `Report' section (if
present) is executed once and the text report is generated. 
</UL>
<UL>
<LI> All data files are closed and the MODEL terminates. 
</UL>
<hr>
Parent Topic: <A href="http://www.pcigeomatics.com/cgi-bin/pcihlp/MODEL|Language">Language</a><br>
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