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fun_property_xam.cpp

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C++: function Properties: Example and Test

# include <cstdio>
# include <cppad/py/cppad_py.hpp>

bool fun_property_xam(void) {
   using cppad_py::a_double;
   using cppad_py::vec_double;
   using cppad_py::vec_a_double;
   using cppad_py::d_fun;
   using cppad_py::a_fun;
   //
   // initialize return variable
   bool ok = true;
   // ----------------------------------------------------------------------
   int n_ind = 1; // number of independent variables
   int n_dep = 2; // number of dependent variables
   int n_var = 1; // phantom variable at address 0
   int n_op  = 1; // special operator at beginning
   //
   // dimension some vectors
   vec_double x(n_ind);
   vec_a_double ay(n_dep);
   //
   // independent variables
   x[0]            = 1.0;
   vec_a_double ax = cppad_py::independent(x);
   n_var           = n_var + n_ind; // one for each indpendent
   n_op            = n_op + n_ind;
   //
   // first dependent variable
   ay[0] = ax[0] + ax[0];
   n_var = n_var + 1; // one variable and operator
   n_op = n_op + 1;
   //
   // second dependent variable
   a_double ax0 = ax[0];
   ay[1]        = ax0.sin();
   n_var        = n_var + 2; // two varialbes, one operator
   n_op         = n_op + 1;
   //
   // define f(x) = y
   d_fun f(ax, ay);
   n_op     = n_op + 1; // speical operator at end
   //
   // check f properties
   ok = ok && f.size_domain() == n_ind;
   ok = ok && f.size_range()  == n_dep;
   ok = ok && f.size_var()    == n_var;
   ok = ok && f.size_op()     == n_op;
   ok = ok && f.size_order()  == 0;
   //
   // compute zero order Taylor coefficients
   vec_double y  = f.forward(0, x);
   ok = ok && f.size_order() == 1;
   //
   // create an a_fun object
   a_fun af(f);
   //
   // ----------------------------------------------------------------------
   // check af properties
   ok = ok && af.size_domain() == n_ind;
   ok = ok && af.size_range()  == n_dep;
   ok = ok && af.size_var()    == n_var;
   ok = ok && af.size_op()     == n_op;
   ok = ok && af.size_order()  == 0;
   // ----------------------------------------------------------------------
   // The empty function
   ax.resize(0);
   ay.resize(0);
   d_fun g(ax, ay);
   ok = ok && g.size_domain() == 0;
   ok = ok && g.size_range()  == 0;
   ok = ok && g.size_var()    == 0;
   ok = ok && g.size_op()     == 0;
   ok = ok && g.size_order()  == 0;
   //
   return( ok  );
}