# Example: poses_quaternions_exampleΒΆ

C++ example source code:

```/* +------------------------------------------------------------------------+
|                     Mobile Robot Programming Toolkit (MRPT)            |
|                          https://www.mrpt.org/                         |
|                                                                        |
| Copyright (c) 2005-2021, Individual contributors, see AUTHORS file     |
| Released under BSD License. See: https://www.mrpt.org/License          |
+------------------------------------------------------------------------+ */

#include <mrpt/math/CQuaternion.h>
#include <mrpt/poses/CPose3D.h>
#include <mrpt/poses/CPose3DQuat.h>

#include <iostream>

using namespace mrpt;
using namespace mrpt::poses;
using namespace mrpt::math;
using namespace std;

// ------------------------------------------------------
//              TestQuaternions
// ------------------------------------------------------
void TestQuaternions()
{
CQuaternionDouble q1, q2, q3;

// q1 = CQuaternionDouble(1,2,3,4); q1.normalize();
CPose3D p1(0, 0, 0, 10.0_deg, 30.0_deg, -20.0_deg);
p1.getAsQuaternion(q1);

CPose3D p2(0, 0, 0, 30.0_deg, -20.0_deg, 10.0_deg);
p2.getAsQuaternion(q2);

// q3 = q1 x q2
q3.crossProduct(q1, q2);

const CPose3D p3 = p1 + p2;

cout << "q1 = " << q1 << endl;
cout << "q1 as CPose3D = " << CPose3D(q1, 0, 0, 0) << endl;
cout << endl;
cout << "q2 = " << q2 << endl;
cout << "q2 as CPose3D = " << CPose3D(q2, 0, 0, 0) << endl;
cout << endl;
cout << "q3 = q1 * q2 = " << q3 << endl;
cout << "q3 as CPose3D = " << CPose3D(q3, 0, 0, 0) << endl;

cout << endl << "Should be equal to p3 = p1 (+) p2 = " << p3 << endl;
}

void TestQuaternionsIterators()
{
CPose3DQuat q(1.0, 2.0, 3.0, CQuaternionDouble());

cout << "Dump with iterators: ";
for (CPose3DQuat::iterator it = q.begin(); it != q.end(); ++it)
cout << *it << " ";
cout << endl;
}

int main(int argc, char** argv)
{
try
{
TestQuaternions();
TestQuaternionsIterators();

return 0;
}
catch (const std::exception& e)
{
std::cerr << "MRPT error: " << mrpt::exception_to_str(e) << std::endl;
return -1;
}
catch (...)
{
printf("Another exception!!");
return -1;
}
}```