\(\newcommand{\W}[1]{ \; #1 \; }\) \(\newcommand{\R}[1]{ {\rm #1} }\) \(\newcommand{\B}[1]{ {\bf #1} }\) \(\newcommand{\D}[2]{ \frac{\partial #1}{\partial #2} }\) \(\newcommand{\DD}[3]{ \frac{\partial^2 #1}{\partial #2 \partial #3} }\) \(\newcommand{\Dpow}[2]{ \frac{\partial^{#1}}{\partial {#2}^{#1}} }\) \(\newcommand{\dpow}[2]{ \frac{ {\rm d}^{#1}}{{\rm d}\, {#2}^{#1}} }\)

graph_unary_op.cpp

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Graph Unary Operator: Example and Test

Source Code

# include <cppad/cppad.hpp>

bool unary_op(void)
{   bool ok = true;
    using std::string;
    double eps99 = 99.0 * std::numeric_limits<double>::epsilon();
    //
    // AD graph example
    // node_1 : p[0]
    // node_2 : x[0]
    // node_3 : c[0]
    // node_4 : sin(p[0])
    // node_5 : sin(x[0])
    // node_6 : sin(c[0])
    // node_7 : sin(p[0]) + sin(x[0]) + sin(c[0])
    // y[0]   = sin(p[0]) + sin(x[0]) + sin(c[0])
    //
    // C++ graph object
    CppAD::cpp_graph graph_obj;
    //
    // operator being used
    CppAD::graph::graph_op_enum op_enum;
    //
    // set scalars
    graph_obj.function_name_set("unary_op example");
    size_t n_dynamic_ind = 1;
    graph_obj.n_dynamic_ind_set(n_dynamic_ind);
    size_t n_variable_ind = 1;
    graph_obj.n_variable_ind_set(n_variable_ind);
    graph_obj.constant_vec_push_back( -0.1 );
    //
    // node_4 : sin(p[0])
    op_enum = CppAD::graph::sin_graph_op;
    graph_obj.operator_vec_push_back(op_enum);
    graph_obj.operator_arg_push_back(1);
    //
    // node_5 : sin(x[0])
    graph_obj.operator_vec_push_back(op_enum);
    graph_obj.operator_arg_push_back(2);
    //
    // node_6 : sin(c[0])
    graph_obj.operator_vec_push_back(op_enum);
    graph_obj.operator_arg_push_back(3);
    //
    // node_7 : sin(p[0]) + sin(x[0]) + sin(c[0])
    //
    // n_arg comes before first_node
    graph_obj.operator_arg_push_back(3);
    // op_enum
    op_enum = CppAD::graph::sum_graph_op;
    graph_obj.operator_vec_push_back(op_enum);
    graph_obj.operator_arg_push_back(4);
    graph_obj.operator_arg_push_back(5);
    graph_obj.operator_arg_push_back(6);
    //
    // y[0]   = sin(p[0]) + sin(x[0]) + sin(c[0])
    graph_obj.dependent_vec_push_back(7);
    //
    // f(x, p) = sin(p_0) + sin(x_0) + sin(c_0)
    CppAD::ADFun<double> f;
    f.from_graph(graph_obj);
    ok &= f.Domain() == 1;
    ok &= f.Range() == 1;
    ok &= f.size_dyn_ind() == 1;
    //
    // value of constant in function
    CPPAD_TESTVECTOR(double) c(1);
    c[0] = -0.1;
    //
    // set independent variables and parameters
    CPPAD_TESTVECTOR(double) p(1), x(1);
    p[0] = 0.2;
    x[0] = 0.3;
    //
    // compute y = f(x, p)
    f.new_dynamic(p);
    CPPAD_TESTVECTOR(double) y = f.Forward(0, x);
    //
    // check result
    double check = std::sin(p[0]) + std::sin(x[0]) + std::sin(c[0]);
    ok &= CppAD::NearEqual(y[0], check, eps99, eps99);
    // -----------------------------------------------------------------------
    // Convert to Graph graph and back again
    f.to_graph(graph_obj);
    f.from_graph(graph_obj);
    // -----------------------------------------------------------------------
    //
    // compute y = f(x, p)
    f.new_dynamic(p);
    y = f.Forward(0, x);
    //
    // check result
    ok &= CppAD::NearEqual(y[0], check, eps99, eps99);
    //
    return ok;
}