# Programming 11/12: VB Assignment 4 – Principal Angle

You will write a program that calculates the principal angle given any co-terminal angle. The principal angle is any angle between 0° inclusive and 360° exclusive, i.e. 0° ≤ θ < 360°. A co-terminal angle can be any angle, possibly negative or larger than 360°, that share the same position as the principal angle.

In general, in order to find the principal angle, you need to either keep adding or keep subtracting the co-terminal angle by 360° until the angle is between 0° and 360°.

Examples:

 Co-Terminal Angle Principal Angle Reason -30° 330° -30° + 360° one cycle forward 400° 40° 400° – 360° one cycle back 800° 80° 800° – 360° = 440° 440° – 360° = 80° two cycles back 360° 0° 360° – 360° one cycle back 100° 100° no movement

Beyond these stated test cases, you need to create you own test cases. The teacher will run through a battery of eight test cases (including some from above) to test your program.

Evaluation: 10 marks

• Test Cases (5 marks)
• Program Code–must use loops (3 marks)
• Flow Chart (2 marks)