# Notation for angle wrapping

1. Sep 29, 2013

### billiards

Hi I am looking for the proper notation to represent angle wrapping in a mathematical function.

For example if I have a function of the form:

y=exp(θ)

(and θ is an angle in degrees.)

How do I write this function to explicitly assert that: -180 ≤ θ < 180 ?

So that for example if one had an angle of numerical value 190, then θ = -170.

2. Sep 29, 2013

### arildno

Take your number A, divide it by 360. If the new number's absolute value is less than or equal to 1/2, keep the number A. Otherwise, subtract 360 from A if it's positive, add 360 if A is negative. Then repeat process with division by 360.

3. Sep 29, 2013

### billiards

Sure. To be clear though, I'm not looking for the numerical recipe. I'm looking for the notation. How would one write this in a formula?

i.e.

$y = exp(\theta)$

would be written like how, something like this??? :

$y = exp([\theta]^{180}_{-180})$ ?????

4. Sep 29, 2013

### arildno

5. Sep 29, 2013

### Office_Shredder

Staff Emeritus
I would just state explicitly as a sentence "for angles between -180 and 180, define y as...."