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

Here is my contribution. It seems to work for all angles with no edge issues. It is fast. It can do n180[360000359] = -1 almost instantaneously. Notice how the Sign function helps select the correct logic path and allows the same code to be used for different angles.

Ratch

n180[a_] := 
 If[Abs[Mod[a, If[Sign[a] == 0, 360, Sign[a] 360]]] <= 180, 
  Mod[a, If[Sign[a] == 0, 360, Sign[a] 360]], 
  Mod[a, If[Sign[a] == 0, 360, -Sign[a] 360]]]