Getting NaN error as the result

Getting NaN error as the result

I seem to be getting a NaN error as the result in my JavaScript code.

I'm pretty new to this, would appreciate any help.

Solved by giving value to the total var.

Answer by simonzack for Getting NaN error as the result

There are a couple of problems:

• You should use parseFloat instead of using strings.
• You should initialize total (this is what causes the nan)
• You should initialize arrays properly.

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function tax() {      var price = new Array(10);      var quant = new Array(10);      var taxam = 18;      var total = 0;      for(i=0;i<10;i++) {          quant[i] = parseFloat(prompt("Insert Quantity: "));          price[i] = parseFloat(prompt("Insert Price: "));      }      for(i=0;i<10;i++) {          total += price[i] * quant[i];      }      total = total * (taxam / 100);      alert(total);  }  

Answer by Daniel 976034 for Getting NaN error as the result

You have to parse the String variables to a Number:

function tax() {    var price = [10];  var quant = [10];  var taxam = 18;  var total = 0;     for(i=0;i<10;i++) {        quant[i] = Number(prompt("Insert Quantity: "));        price[i] = Number(prompt("Insert Price: "));        }    for(i=0;i<10;i++) {    total += price[i] * quant[i];     }    total = total * (taxam / 100);    alert(total);      }  tax()  

Answer by Ade for Getting NaN error as the result

I guess with this var price = [10] you were trying to create an array with 10 numbers, but that is not the way it works in Javascript var price = [10] will give you an array with 10 at the 0th position. The only other tweak I would make there is make var price = [1,2,3,4,5,6,7,8,9,10] to actually achieve what you set out for initally

Answer by Miam84 for Getting NaN error as the result

First of all, JavaScript is not Java ;)

You seem to try to initialize your arrays with a length of 10. This works in Java but in Javascript an array is dynamic and writing :

myArray = [10];  

will just set the value 10 in the first index of the array.

Then, as you prompt the user to input numbers, the numbers will be interpreted as a string. So it would be good to cast it to a number before working with it. To cast it :

var value = '10000';  valueAsInt = parseFloat('10000',10);  //or simply   valueAsInt = +value;  

Now we come to your problem, as total is not initialised, the first affectation will be

undefined += n;  

this will give a NaN.

So just initialise total before using it :

var total = 0;  

Answer by ojus kulkarni for Getting NaN error as the result

you have to initialize total variable first because it is undefined initially

var total = 0;  

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