My goal is to find all the unique years in this array and than return it as a array. I have almost done it but cant figure out how I will return the split value.
function findUniqueYears() {
const arr = ['1973-11-01', '2001-01-01', '1999-10-01', '2007-10-01', '2016-06-01', '2005-08-01', '1973-09-01', '1979-12-01', '2001-08-01'];
for (var i = 0; i < arr.length; i++) {
for (var j = i + 1; j < arr.length; j++) {
if (arr[i].split("-")[0] === arr[j].split("-")[0]) {
arr.splice(j, 1);
}
}
}
console.log(arr)
}
This should do
const findUniqueYears = (arr) => Array.from(new Set(arr.map(item => item.split('-')[0])))
You can use the function map to iterate via each element in the array then you can easily split date by '-' return 0 value and cast it to Set.
function findUniqueYears() {
const arr = ['1973-11-01', '2001-01-01', '1999-10-01', '2007-10-01', '2016-06-01', '2005-08-01', '1973-09-01', '1979-12-01', '2001-08-01'];
return new Set(arr.map((el) => el.split('-')[0]))
}