Remove duplicates and mirror from [x,y] coordinates

April 20, 2022

let x=[1,2,6,3,5,5,5,4,4];

let y=[3,4,3,5,2,4,4,2,6];

expected_x=[1,2,6,3,5,5,4]

expected_y=[3,4,3,5,2,4,6]

Think of x and y as coordinates.[1,3] will be first point and [4,6] will be last point.

If a [X,Y] has duplicates, only one of the [X,Y] will be displayed in the expected output (no duplicate). And if, there is a mirror like [X,Y] which is a mirror of [Y,X] with both at the same index.

This is the code I have written for just one array to make the array unique. However, I am unsure on how to use it with 2 seperate arrays representing x and y coordinates. Any help will be appreciated 🙂

let chars = ['A', 'B', 'A', 'C', 'B'];
let uniqueChars = [...new Set(chars)];

console.log(uniqueChars);

>Solution :

Use this:

let x=[1,2,6,3,5,5,5,4,4];
let y=[3,4,3,5,2,4,4,2,6];
const coordinates = [];
let i = -1;

while ( x[++i] ) { 
  const c = [x[i], y[i]]
  coordinates.push(c);
}
const coordArray = coordinates.reduce((p, next) => {
  if (!p.includes(JSON.stringify(next)) && !p.includes(JSON.stringify([...next].reverse()))) {
    p.push(JSON.stringify(next));
  }
  return p;
},[]).map(JSON.parse)
console.log(coordArray)