Json sum Operator: Example and Test

json_sum_op.cpp

@(@\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}} }@)@This is cppad-20221105 documentation. Here is a link to its current documentation . Json sum Operator: Example and Test
Source Code


# include <cppad/cppad.hpp>

bool sum_op(void)
{   bool ok = true;
    using CppAD::vector;
    using CppAD::AD;
    //
    // AD graph example
    // node_1 : p[0]
    // node_2 : p[1]
    // node_3 : p[2]
    // node_4 : x[0]
    // node_5 : p[0] + p[1] + p[2]
    // node_6 : x[0] + p[0] + p[1] + p[2]
    // y[0]   = x[0] + p[0] + p[1] + p[2]
    // use single quote to avoid having to escape double quote
    std::string json =
        "{\n"
        "   'function_name'  : 'sum_op example',\n"
        "   'op_define_vec'  : [ 2, [\n"
        "       { 'op_code':1, 'name':'add', 'n_arg':2 } ,\n"
        "       { 'op_code':2, 'name':'sum' } ]\n"
        "   ],\n"
        "   'n_dynamic_ind'  : 3,\n"
        "   'n_variable_ind' : 1,\n"
        "   'constant_vec'   : [ 0, [ ] ],\n"
        "   'op_usage_vec'   : [ 2, [\n"
        "       [ 2, 1, 3, [1, 2, 3] ] ,\n" // p[0] + p[1] + p[2]
        "       [ 2, 1, 2, [4, 5 ]   ] ]\n" // x[0] + p[0] + p[1] + p[2]
        "   ],\n"
        "   'dependent_vec' : [ 1, [6] ] \n"
        "}\n";
    // Convert the single quote to double quote
    for(size_t i = 0; i < json.size(); ++i)
        if( json[i] == '\'' ) json[i] = '"';
    //
    // f(x, p) = x_0 + p_0 + p_1 + p_2
    CppAD::ADFun<double> f;
    f.from_json(json);
    //
    ok &= f.Domain() == 1;
    ok &= f.Range() == 1;
    ok &= f.size_dyn_ind() == 3;
    //
    // set independent variables and parameters
    vector<double> p(3), x(1);
    for(size_t j = 0; j < 3; ++j)
        p[j] = double(j + 1);
    x[0] = 5.0;
    //
    // compute y = f(x, p)
    f.new_dynamic(p);
    vector<double> y = f.Forward(0, x);
    //
    // check result
    ok &= y[0] == x[0] + p[0] + p[1] + p[2];
    // -----------------------------------------------------------------------
    // Convert to Json graph and back again
    json = f.to_json();
    // std::cout << "json = " << json;
    f.from_json(json);
    // -----------------------------------------------------------------------
    ok &= f.Domain() == 1;
    ok &= f.Range() == 1;
    ok &= f.size_dyn_ind() == 3;
    //
    // set independent variables and parameters
    for(size_t j = 0; j < 3; ++j)
        p[j] = double(j + 1);
    x[0] = 5.0;
    //
    // compute y = f(x, p)
    f.new_dynamic(p);
    y = f.Forward(0, x);
    //
    // check result
    ok &= y[0] == x[0] + p[0] + p[1] + p[2];
    //
    return ok;
}

Input File: example/json/sum_op.cpp