Given a degree x, find the nearest degree in an array of degrees?

Question

I have an array of degrees, [10, 90, 200, 280, 355] for a circle. I'm given a degree, let's say 1. How do I determine that 1 is closest to 355 degrees?

Answer 1

function closestDegreeFinder(x, degrees) {

//make a copy of degrees

let arr = [...degrees]

//Keep track of the position of the degree you want to return

//and the distance

let index = 0

let closestDistance = Infinity

//loop through array

for(let i = 0; i < arr.length; i++){

//Handle degrees greater than 360

while(arr[i] > 360){

arr[i] -= 360

}

//Calculate the absolute distance between the degree in

//the array and the given degree

let distance = Math.abs(arr[i] - x)

//if the distance is greater than 180, then the distance would

//be shorter ifwe calculate it from the other direction.

//In that case, subtract 360 from the distance and get

//its absolute value. Assign that value as the new

//shorter distance

if(distance > 180){

distance = Math.abs(distance - 360)

}

//if the distance is lower than the distance we thought

//was the closest, then that new distance is the closest

if(distance < closestDistance){

closestDistance = distance

index = i

}

}

//return the closest degree

return arr[position]

}

console.log(closestDegreeFinder(1, [10, 90, 200, 280, 355]))