Compute Altitude and Azimuth using either Quaternions or Rotation Matrix or Roll, Pitch and Yaw component

Question

I am struck with a mathematical problem. I want to convert the iPhone device's attitude information which is available in one of the following forms:

1. Quaternion
2. Rotation Matrix
3. Roll, Pitch and Yaw component

To, Altitude and Azimuth. Where:

• Altitude should be between: 0 to 90 deg and / or 0 to -90 deg. which depicts the altitude of the object pointed by the device in the sky.

• Azimuth between 0 to 360 deg. which depicts the direction. North being 0 deg, South being 180 deg. etc.

I am no expert at mathematics, so guys help me in figuring out this problem. I have already posted this question in sister website without much help. Probably because it involves too much of mathematics.

Thanks & Regards,

Raj