Let's assume that we are working with the following array:
javascriptlet array = ['Erik', 'Andrea', 'Paula', 'Erik', 'Andrea'];
If we want to count the occurrences (frequency) of the array elements:
javascript// Object to count occurrences let counter = {}; // If name exists, we add 1 occurrence, otherwise we set counter to 1 array.forEach(name => counter[name] ? counter[name] ++ : counter[name] = 1); console.log(counter); // {Erik: 2, Andrea: 2, Paula: 1}
If we want to find the highest duplicate value(s):
javascript// Getting max number of occurrences let max = Math.max(...Object.values(counter)); // Getting array of highest duplicate values let highest = Object.entries(counter).filter(([name, reps]) => reps === max); console.log(highest); // [['Erik', 2], ['Andrea', 2]]
Hi, I'm Erik, an engineer from Barcelona. If you like the post or have any comments, say hi.