Uncaught TypeError: Cannot read properties of undefined (reading 'length') in Javascript

Question

I'm trying to remove the entire sub-array from arr if any of the items equal to elem.

Here's the code

function filteredArray(arr, elem) {
   for (let i = 0; i < arr.length; i++) {
      for (let j = 0; j < arr[i].length; j++) {
         if (arr[i][j] === elem) {
           arr.splice(i, 1);
         }
       }
    }
    return newArr = [...arr];
}

console.log(filteredArray([[3, 2, 3], [1, 6, 3], [3, 13, 26], [19, 3, 9]], 3));

If I remove the condition in the IF statement, the error disappears. Why is the condition in the If statement causing the error?

I'm trying to understand why the error is coming up so that I will not repeat it again

score 1 · Answer 1 · answered Oct 12 '22 at 14:25

Just use filter and check with includes if the subArray contain the elem

function filteredArray(arr, elem) {
   return arr.filter(subArr => !subArr.includes(elem))
}

console.log(filteredArray([[3, 2, 3], [1, 6, 3], [3, 13, 26], [19, 3, 9]], 3));
console.log(filteredArray([[3, 2, 3], [1, 6, 3], [2, 13, 26], [19, 4, 9]], 3));

Uncaught TypeError: Cannot read properties of undefined (reading 'length') in Javascript

1 Answers1