Finding the most frequently occuring element in a array

[jamesloacher]

How can I find the most frequently occuring element in an array of numbers?
I'm lost on this one.

[jamesloacher]

Like if I had this array

code:

---

var myNums:Array = [4,65,33,22,4,7,54,98,54,65,4];

---

Or any numbers 4 is the one occuring the most often how could I write a function to return the most occuring number?

[Boris the Frog]

//message removed

[Boris the Frog]

this code uses an array called 'testArray' that contains letters, but this just makes illustrating how it works easier - you can replace these with numbers if you want.
The showArray function lists the unique items from testarray, as well as a count for the number of times each item is listed in testArray

var testArray:Array = new Array("a", "b", "c", "d", "a", "b", "e", "g");
//
function findNumItemsInArray(findIn:Array) {
	//the tmpArray will hold at [0], a list on unique items in findIn array
	//tmpArray[x] = a number recording the instance in FindIn array of the number at tmpArray[0][x]
	var tmpArray:Array = new Array();
	tmpArray[0] = new Array();
	//
	for (var i = 0; i<findIn.length; i++) {
		var str:String = tmpArray[0].toString();
		//str needs the "," removed
		str = removeDelimiters(str, ",");
		//find index of current num in tmpArray[0]
		var searchFor = findIn[i];
		var indexPos:Number = str.indexOf(searchFor);
		if (indexPos == -1) {
			//it's not found in the tmpArray, so add it
			tmpArray[0].push(searchFor);
			tmpArray.push(1);
		} else {
			//it's been found, so increment the count
			tmpArray[indexPos+1]++;
		}
	}
	showArray(tmpArray);
}
function showArray(ar:Array) {
	for (var i = 0; i<ar.length; i++) {
		trace("Array["+i+"]: "+ar[i]);
	}
}
//
function removeDelimiters(str:String, del:String):String {
	var strArray:Array = str.split(del);
	var newStr:String = "";
	for (var i = 0; i<strArray.length; i++) {
		newStr += strArray[i];
	}
	return (newStr);
}
findNumItemsInArray(testArray);

Although this doesn't tell you the MOST occuring item in the array you can now easily detect it from the tmpArray result
hope this helps

[Boris the Frog]

You can add this function:

function findmostfrequent(ar:Array) {
	//search through the arry from 1 up = find the highest number and return the index from [0] of it
	var highest:Array = new Array(0, -1);
	for (var i = 1; i<=ar.length; i++) {
		if (ar[i] > highest[0]){
			highest[0] = ar[i];
			highest[1] = i;
		}
	}
	trace("The most frequently occuring item in the array is " + ar[0][highest[1]]);
	trace("It occurs " + highest[0] + " times");
}

and call :

findmostfrequent(tmpArray);

as the last line of findNumItemsInArray function

[a_modified_dog]

another method of finding the most frequently occuring element in an array

 arr1 = [4,65,33,22,4,7,22,54,98,54,65,4];

 arr2 = ['tuba','trombone','saxophone','trombone',
'saxophone','tuba','trombone','tuba','trombone'];

Array.prototype.count = function(element){
var n = 0;
var i = this.length;
while(i--){
if(this[i]==element) n++;
}
return n;
}

trace(arr1.count(4)); // 3
trace(arr1.count(22)); // 2
trace(arr2.count('tuba')); // 3
trace(arr2.count('trombone')); // 4

my 2c's -- hth

[jamesloacher]

Thank you both for taking the time to help me. I was able to get it working. So thanks.