The following code example is taken from the book
The C++ Standard Library - A Tutorial and Reference, 2nd Edition
by Nicolai M. Josuttis, Addison Wesley Longman, 2012
Copyright © 2012 by Pearson Education, Inc. and Nicolai M. Josuttis
#include <iostream>
#include <complex>
using namespace std;
int main()
{
// complex number with real and imaginary parts
// - real part: 4.0
// - imaginary part: 3.0
complex<double> c1(4.0,3.0);
// create complex number from polar coordinates
// - magnitude: 5.0
// - phase angle: 0.75
complex<float> c2(polar(5.0,0.75));
// print complex numbers with real and imaginary parts
cout << "c1: " << c1 << endl;
cout << "c2: " << c2 << endl;
// print complex numbers as polar coordinates
cout << "c1: magnitude: " << abs(c1)
<< " (squared magnitude: " << norm(c1) << ") "
<< " phase angle: " << arg(c1) << endl;
cout << "c2: magnitude: " << abs(c2)
<< " (squared magnitude: " << norm(c2) << ") "
<< " phase angle: " << arg(c2) << endl;
// print complex conjugates
cout << "c1 conjugated: " << conj(c1) << endl;
cout << "c2 conjugated: " << conj(c2) << endl;
// print result of a computation
cout << "4.4 + c1 * 1.8: " << 4.4 + c1 * 1.8 << endl;
// print sum of c1 and c2:
// - note: different types
cout << "c1 + c2: "
<< c1 + complex<double>(c2.real(),c2.imag()) << endl;
// add square root of c1 to c1 and print the result
cout << "c1 += sqrt(c1): " << (c1 += sqrt(c1)) << endl;
}