Function run_test06

exprtk_test.cpp:3396–3443

template <typename T>
bool run_test06()
{
   typedef exprtk::expression<T> expression_t;

   const std::string expression_string = "sqrt(1 - (x^2))";

   T x = T(0);

   exprtk::symbol_table<T> symbol_table;
   symbol_table.add_variable("x",x);

   expression_t expression;
   expression.register_symbol_table(symbol_table);

   {
      exprtk::parser<T> parser;

      if (!parser.compile(expression_string,expression))
      {
         printf("run_test06() - Error: %s   Expression: %s\n",
                parser.error().c_str(),
                expression_string.c_str());

         return false;
      }
   }

   T total_area1 = exprtk::integrate(expression,x,T(-1),T(1));
   T total_area2 = exprtk::integrate(expression,"x",T(-1),T(1));
   const T pi = T(3.141592653589793238462643383279502);

   if (not_equal(total_area1,total_area2,T(0.000001)))
   {
      printf("run_test06() - Integration Error:  area1 != area2\n");
      return false;
   }

   if (not_equal(total_area1,T(pi) / T(2),T(0.000001)))
   {
      printf("run_test06() - Integration Error:  Expected: %19.15f\tResult: %19.15f\n",
             static_cast<double>(pi / T(2)),
             static_cast<double>(total_area1));

      return false;
   }

   return true;
}

template <typename T>
bool run_test07()