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AD Output Operator: Example and Test
 

# include <cppad/cppad.hpp>

# include <sstream>  // std::ostringstream
# include <string>   // std::string
# include <iomanip>  // std::setprecision, setw, setfill, right

namespace {
	template <class S>
	void set_ostream(S &os)
	{	os 
		<< std::setprecision(4) // 4 digits of precision
		<< std::setw(6)         // 6 characters per field
		<< std::setfill(' ')    // fill with spaces
		<< std::right;          // adjust value to the right
	}
}

bool Output(void)
{	bool ok = true;

	// This output stream is an ostringstream for testing purposes.
	// You can use << with other types of streams; i.e., std::cout.
	std::ostringstream stream;

	// ouput an AD<double> object
	CppAD::AD<double>  pi = 4. * atan(1.); // 3.1415926536
	set_ostream(stream);
	stream << pi;

	// ouput a VecAD<double>::reference object
	CppAD::VecAD<double> v(1);
	CppAD::AD<double> zero(0);
	v[zero]   = exp(1.);                  // 2.7182818285
	set_ostream(stream); 
	stream << v[zero];

	// convert output from stream to string
	std::string str = stream.str();

	// check the output
	ok      &= (str == " 3.142 2.718");

	return ok;
}

Input File: example/output.cpp