Easy way to keeping angles between -179 and 180 degrees

Question

Is there an easy way to convert an angle (in degrees) to be between -179 and 180? I\'m sure I could use mod (%) and some if statements, but it gets ugly:

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Answer 1

// reduce the angle  
angle =  angle % 360; 

// force it to be the positive remainder, so that 0 <= angle < 360  
angle = (angle + 360) % 360;  

// force into the minimum absolute value residue class, so that -180 < angle <= 180  
if (angle > 180)  
    angle -= 360;