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<center><b><big><big>AD Binary Comparison Operators: Example and Test</big></big></b></center>
<code><font color="blue"><pre style='display:inline'> 
# include &lt;cppad/cppad.hpp&gt;

bool Compare(void)
{	bool ok = true;
	using CppAD::AD;
	using CppAD::NearEqual;

	// declare independent variables and start tape recording
	size_t n  = 2;
	double x0 = 0.5;
	double x1 = 1.5;
	<a href="testvector.xml" target="_top">CPPAD_TESTVECTOR</a>(AD&lt;double&gt;) x(n);
	x[0]      = x0; 
	x[1]      = x1; 
	CppAD::<a href="independent.xml" target="_top">Independent</a>(x);

	// some binary comparision operations
	<a href="ad.xml" target="_top">AD</a>&lt;double&gt; p;
	if( x[0] &lt; x[1] )
		p = x[0];   // values in x choose this case
	else	p = x[1];
	if( x[0] &lt;= x[1] )
		p *= x[0];  // values in x choose this case
	else	p *= x[1];
	if( x[0] &gt;  x[1] )
		p *= x[0]; 
	else	p *= x[1];  // values in x choose this case
	if( x[0] &gt;= x[1] )
		p *= x[0]; 
	else	p *= x[1];  // values in x choose this case
	if( x[0] == x[1] )
		p *= x[0]; 
	else	p *= x[1];  // values in x choose this case
	if( x[0] != x[1] )
		p *= x[0];  // values in x choose this case
	else	p *= x[1]; 

	// dependent variable vector 
	size_t m = 1;
	<a href="testvector.xml" target="_top">CPPAD_TESTVECTOR</a>(AD&lt;double&gt;) y(m);
	y[0] = p;

	// create f: x -&gt; y and stop tape recording
	CppAD::<a href="funconstruct.xml" target="_top">ADFun</a>&lt;double&gt; f(x, y); 

	// check value 
	ok &amp;= <a href="nearequal.xml" target="_top">NearEqual</a>(y[0] , x0*x0*x1*x1*x1*x0,  1e-10 , 1e-10);

	// forward computation of partials w.r.t. x[0]
	<a href="testvector.xml" target="_top">CPPAD_TESTVECTOR</a>(double) dx(n);
	<a href="testvector.xml" target="_top">CPPAD_TESTVECTOR</a>(double) dy(m);
	dx[0] = 1.;
	dx[1] = 0.;
	dy    = f.<a href="forward.xml" target="_top">Forward</a>(1, dx);
	ok   &amp;= <a href="nearequal.xml" target="_top">NearEqual</a>(dy[0], 3.*x0*x0*x1*x1*x1, 1e-10, 1e-10);

	// forward computation of partials w.r.t. x[1]
	dx[0] = 0.;
	dx[1] = 1.;
	dy    = f.<a href="forward.xml" target="_top">Forward</a>(1, dx);
	ok   &amp;= <a href="nearequal.xml" target="_top">NearEqual</a>(dy[0], 3.*x0*x0*x1*x1*x0, 1e-10, 1e-10);

	// reverse computation of derivative of y[0]
	<a href="testvector.xml" target="_top">CPPAD_TESTVECTOR</a>(double)  w(m);
	<a href="testvector.xml" target="_top">CPPAD_TESTVECTOR</a>(double) dw(n);
	w[0]  = 1.;
	dw    = f.<a href="reverse.xml" target="_top">Reverse</a>(1, w);
	ok   &amp;= <a href="nearequal.xml" target="_top">NearEqual</a>(dw[0], 3.*x0*x0*x1*x1*x1, 1e-10, 1e-10);
	ok   &amp;= <a href="nearequal.xml" target="_top">NearEqual</a>(dw[1], 3.*x0*x0*x1*x1*x0, 1e-10, 1e-10);

	return ok;
}

</pre>

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<hr/>Input File: example/compare.cpp

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