Sum numbers in an Array ? w/ solution

Or you can use "isNaN()" function to identify non-numeric and undefined elements in the array. Wrapping this in a callable funciton:

function SumArray(aItem) {
var sum = 0;
for (i = 0; i < aItem.length; i++) {
if ( !isNaN(aItem[i]) ) { //drop NaN items - Not isNaN()
sum += Number(aItem[i]); // add as number
}
return sum; // return the computed sum
}


var y = new Array(4);
y[0] = 3;
y[2] = 7 ;
y[1] = 5 ;

var x = this.getField("detail.0") ;
x.value = SumArray(y);

A more extensive example of the use of "Number()" and "isNaN()" and accessing elements in an array by index number and by active element. Also an example of using test named elements rather than the number index.

var aTable = new Array(12);
aTable[0] = 1;
aTable[2] = 3;
aTable[5] = "a"; // character string
aTable[7] = "4"; // number as a string
aTable["Alpha"] = "Text";
aTable["Number"] = 8;
console.println("Size of aTalbe: " + aTable.length);
var sum = 0;
var sumA = 0;
var sumN = 0;
console.println("by index:");
for (i = 0; i < aTable.length; i++) {
console.println(i + " = " + aTable[i] + " type of: " + typeof aTable[i] + " isNaN: " + isNaN(aTable[i]) );
sum += aTable[i];
if (!isNaN(aTable[i]) ) sumA += Number(aTable[i]);
if (!isNaN(aTable[i]) ) sumN += Number(aTable[i]);
}
console.println("plain sum: " + sum);
console.println("isNaN constricted sum: " + sumA);
console.println("number constricted sum: " + sumN);
console.println("");
console.println("By element:");
sum = 0;
sumA = 0;
sumN = 0;
for (i in aTable) {
console.println(i + " = " + aTable[i] + " type of: " + typeof aTable[i] + " isNaN: " + isNaN(aTable[i]) );
sum += aTable[i];
if (!isNaN(aTable[i]) ) sumA += aTable[i];
if (!isNaN(aTable[i]) ) sumN += Number(aTable[i]);
}
console.println("plain sum: " + sum);
console.println("isNaN constricted sum: " + sumA);
console.println("isNaN & number constricted sum: " + sumN);