# Snippet Angles: Clockwise

Discussion in 'Tutorials and Resources' started by Dirac, Feb 3, 2012.

1. ### Dirac22710180

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JASS:
``````//Determines if "a" gets closer to "b" by going clockwise.
function Clockwise takes real a, real b returns boolean
return Sin(b-a)<=0
endfunction``````

Example:
Lets take 2 angles, lets say 90 and 330 The function `Clockwise(90,330)` returns true, because 90 is closer to 330 by going clockwise.

Explanation:
`Sin(330-90) - > Sin(240) == -0.866`
The result is negative, the function returns true.
"Sin" is a function that evaluates the position of an angle according to it's image in the Y axis.
So if the angle given is between 180- and 0+ it returns a positive number, but if it's between 180+ and 360- it returns a negative number. So now Imagine comparing 0 to any other given angle. We know that 0 has to go counter-clockwise to reach 30, and Sin(30) is positive, and to reach 330 it has to go clockwise, and Sin(330) is negative.
So basically the function takes the comparison of the two given angles and turns it into comparing the angle to 0.
`Clockwise(90,330)` is the same as `Clockwise(0,240)`