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AD Binary Division: Example and Test
`

    # include <cppad/cppad.hpp>

    bool Div(void)
    {     bool ok = true;
         using CppAD::AD;
         using CppAD::NearEqual;
         double eps99 = 99.0 * std::numeric_limits<double>::epsilon();

         // domain space vector
         size_t n  = 1;
         double x0 = 0.5;
         CPPAD_TESTVECTOR(AD<double>) x(n);
         x[0]      = x0;

         // declare independent variables and start tape recording
         CppAD::Independent(x);

         // some binary division operations
         AD<double> a = x[0] / 1.; // AD<double> / double
         AD<double> b = a  / 2;    // AD<double> / int
         AD<double> c = 3. / b;    // double     / AD<double>
         AD<double> d = 4  / c;    // int        / AD<double>

         // range space vector
         size_t m = 1;
         CPPAD_TESTVECTOR(AD<double>) y(m);
         y[0] = (x[0] * x[0]) / d;   // AD<double> / AD<double>

         // create f: x -> y and stop tape recording
         CppAD::ADFun<double> f(x, y);

         // check value
         ok &= NearEqual(y[0], x0*x0*3.*2.*1./(4.*x0), eps99, eps99);

         // forward computation of partials w.r.t. x[0]
         CPPAD_TESTVECTOR(double) dx(n);
         CPPAD_TESTVECTOR(double) dy(m);
         dx[0] = 1.;
         dy    = f.Forward(1, dx);
         ok   &= NearEqual(dy[0], 3.*2.*1./4., eps99, eps99);

         // reverse computation of derivative of y[0]
         CPPAD_TESTVECTOR(double)  w(m);
         CPPAD_TESTVECTOR(double) dw(n);
         w[0]  = 1.;
         dw    = f.Reverse(1, w);
         ok   &= NearEqual(dw[0], 3.*2.*1./4., eps99, eps99);

         // use a VecAD<Base>::reference object with division
         CppAD::VecAD<double> v(1);
         AD<double> zero(0);
         v[zero] = d;
         AD<double> result = (x[0] * x[0]) / v[zero];
         ok     &= (result == y[0]);

         return ok;
    }

`

Input File: example/general/div.cpp