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<center><b><big><big>OpenMP Maximum Thread Number</big></big></b></center>
<br/>
<b><big><a name="Syntax" id="Syntax">Syntax</a></big></b>
<br/>
<code><font color="blue"><span style='white-space: nowrap'>AD<</span></font></code><i><span style='white-space: nowrap'>Base</span></i><code><font color="blue"><span style='white-space: nowrap'>>::omp_max_thread(</span></font></code><i><span style='white-space: nowrap'>number</span></i><code><font color="blue"><span style='white-space: nowrap'>)<br/>
</span></font></code><br/>
<b><big><a name="Purpose" id="Purpose">Purpose</a></big></b>
<br/>
By default, for each <code><font color="blue"><span style='white-space: nowrap'>AD<</span></font></code><i><span style='white-space: nowrap'>Base</span></i><code><font color="blue"><span style='white-space: nowrap'>></span></font></code> class there is only one
tape that records <a href="glossary.xml#AD of Base" target="_top"><span style='white-space: nowrap'>AD of Base</span></a>
operations.
This tape is a global variable and hence it cannot be used
by multiple OpenMP threads at the same time.
The <code><font color="blue">omp_max_thread</font></code> function is used to set the
maximum number of OpenMP threads that can be active.
In this case, there is a different tape corresponding to each
<code><font color="blue"><span style='white-space: nowrap'>AD<</span></font></code><i><span style='white-space: nowrap'>Base</span></i><code><font color="blue"><span style='white-space: nowrap'>></span></font></code> class and thread pair.
<br/>
<br/>
<b><big><a name="number" id="number">number</a></big></b>
<br/>
The argument <i>number</i> has prototype
<code><font color="blue"><span style='white-space: nowrap'><br/>
     size_t </span></font></code><i><span style='white-space: nowrap'>number</span></i><code><font color="blue"><span style='white-space: nowrap'><br/>
</span></font></code>It must be greater than zero and specifies the maximum number of
OpenMp threads that will be active at one time.
<br/>
<br/>
<b><big><a name="Independent" id="Independent">Independent</a></big></b>
<br/>
Each call to <a href="independent.xml" target="_top"><span style='white-space: nowrap'>Independent(x)</span></a>
creates a new <a href="glossary.xml#Tape.Active" target="_top"><span style='white-space: nowrap'>active</span></a>
tape.
All of the operations with the corresponding variables
must be preformed by the same OpenMP thread.
This includes the corresponding call to
<a href="dependent.xml" target="_top"><span style='white-space: nowrap'>f.Dependent(x,y)</span></a>
or the
<a href="funconstruct.xml#Sequence Constructor" target="_top"><span style='white-space: nowrap'>ADFun f(x, y)</span></a>
during which the tape stops recording and the variables
become parameters.
<br/>
<br/>
<b><big><a name="Restriction" id="Restriction">Restriction</a></big></b>
<br/>
No tapes can be
<a href="glossary.xml#Tape.Active" target="_top"><span style='white-space: nowrap'>active</span></a>
when this function is called.
<br/>
<br/>
<b><big><a name="Example and Tests" id="Example and Tests">Example and Tests</a></big></b>
<br/>
The shell script <a href="openmp_run.sh.xml" target="_top"><span style='white-space: nowrap'>openmp_run.sh</span></a>
can be used to
compile and run the OpenMP examples and tests.
<hr/>Input File: cppad/local/omp_max_thread.hpp
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