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<?xml version='1.0'?>
<html xmlns='http://www.w3.org/1999/xhtml'
      xmlns:math='http://www.w3.org/1998/Math/MathML'
>
<head>
<title>Number of Variables that Can be Skipped</title>
<meta http-equiv='Content-Type' content='text/html' charset='utf-8'/>
<meta name="description" id="description" content="Number of Variables that Can be Skipped"/>
<meta name="keywords" id="keywords" content=" number_skip number skip variables of that can be skipped syntax see also purpose n f example "/>
<style type='text/css'>
body { color : black }
body { background-color : white }
A:link { color : blue }
A:visited { color : purple }
A:active { color : purple }
</style>
<script type='text/javascript' language='JavaScript' src='_number_skip_xml.js'>
</script>
</head>
<body>
<table><tr>
<td>
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</select>
</td>
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<option>seq_property</option>
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</select>
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<option>forward_zero</option>
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<option>forward_dir</option>
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<option>CompareChange</option>
<option>capacity_order</option>
<option>number_skip</option>
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<option>---..See Also</option>
<option>Purpose</option>
<option>n</option>
<option>f</option>
<option>Example</option>
</select>
</td>
</tr></table><br/>








<center><b><big><big>Number of Variables that Can be Skipped</big></big></b></center>
<br/>
<b><big><a name="Syntax" id="Syntax">Syntax</a></big></b>

<br/>

<code><i><font color="black"><span style='white-space: nowrap'>n</span></font></i><font color="blue"><span style='white-space: nowrap'>&#xA0;=&#xA0;</span></font><i><font color="black"><span style='white-space: nowrap'>f</span></font></i><font color="blue"><span style='white-space: nowrap'>.number_skip()</span></font></code>


<br/>
<br/>
<b><a name="Syntax.See Also" id="Syntax.See Also">See Also</a></b>

<br/>
<a href="seq_property.xml" target="_top"><span style='white-space: nowrap'>seq_property</span></a>


<br/>
<br/>
<b><big><a name="Purpose" id="Purpose">Purpose</a></big></b>
<br/>
The <a href="condexp.xml" target="_top"><span style='white-space: nowrap'>conditional&#xA0;expressions</span></a>
 use either the
<a href="condexp.xml" target="_top"><span style='white-space: nowrap'>if_true</span></a>
 or <a href="condexp.xml" target="_top"><span style='white-space: nowrap'>if_false</span></a>
.
This leads to the fact that some terms only need to be evaluated
depending on the value of the comparison in the conditional expression.
The <a href="optimize.xml" target="_top"><span style='white-space: nowrap'>optimize</span></a>
 option is capable of detecting some of these 
case and determining variables that can be skipped.
This routine returns the number such variables.

<br/>
<br/>
<b><big><a name="n" id="n">n</a></big></b>
<br/>
The return value 
<code><i><font color="black"><span style='white-space: nowrap'>n</span></font></i></code>
 has type <code><font color="blue">size_t</font></code>
is the number of variables that the optimizer has determined can be skipped 
(given the independent variable values specified by the previous call to
<a href="forward.xml" target="_top"><span style='white-space: nowrap'>f.Forward</span></a>
 for order zero).

<br/>
<br/>
<b><big><a name="f" id="f">f</a></big></b>
<br/>
The object 
<code><i><font color="black"><span style='white-space: nowrap'>f</span></font></i></code>
 has prototype

<code><font color="blue"><span style='white-space: nowrap'><br/>
&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;ADFun&lt;</span></font><i><font color="black"><span style='white-space: nowrap'>Base</span></font></i><font color="blue"><span style='white-space: nowrap'>&gt;&#xA0;</span></font><i><font color="black"><span style='white-space: nowrap'>f</span></font></i><font color="blue"><span style='white-space: nowrap'><br/>
</span></font></code>
<br/>
<b><big><a name="Example" id="Example">Example</a></big></b>
<br/>
The file <a href="number_skip.cpp.xml" target="_top"><span style='white-space: nowrap'>number_skip.cpp</span></a>

contains an example and test of this function.
It returns true if it succeeds and false otherwise.


<hr/>Input File: cppad/local/num_skip.hpp

</body>
</html>