adding all the numbers in a string

[nathan gibson]

  import java.util.Scanner;
import java.util.Random;
import java.io.IOException;
import java.io.PrintWriter;
import java.io.File;

public class BottleCapPrize
{
    public static void main(String [] args)throws IOException
    {
        Scanner in;  
        in = new Scanner(System.in);
        
        
        int numTrials = 20;
        
        
        PrintWriter outFile = new PrintWriter (new File("bottleCap.txt"));
  
       
   
      for (int i = 0; i < numTrials; i++) 
   
      {
   
      int counter = 0;
   
      int randomNumber = 0; 
  
       
  
      do 
  
      {
  
      randomNumber = ((int)(0+ Math.random()* 5));
  
      counter++;
  
      }
  
      while (randomNumber != 1); 
  
       
  
      outFile.println(counter);
  
      } 
  
       
  
        outFile.close ( );
        
        String token = "";
        File fileName = new File("bottleCap.txt");
        Scanner inFile = new Scanner(fileName);
        while (inFile.hasNext())
        {
         token = inFile.next( );

                  
        }      
        inFile.close();
        
        
        
       
                   
                  


              
           

        }
     }
  

what can i use to add all the numbers in this string token? i need to add them all so i can divide by numTrials and get an average.

[David Newton]

Look at the java.lang.Integer class for one parsing option. I'll reiterate my suggestion to check out Sun's Java tutorials, get a reference book, or search the web: when I used Google to search for "java +convert string to number" I get a *lot* of relevant hits on the first page.

(And consider a code indentation style; it makes things much, much easier to read.)

[nathan gibson]

i am familiar with converting strings to numbers, but that is not what i am trying to do, im trying to see if there is another method because i have to up the number of trial to 1000 and that is way to many variable to make.

[nathan gibson]

also its pretty hard to search google for something if you dont know what something is, i did google, and all i got is string methods in the apis that werent what i was looking for.

[Fred Hamilton]

Here's another way. If you mean that each character in the string represents a separate digit, then you can isolate each character and treat it as an integer by using a simple arithmetic expression. Have a look at the following page, and pay particular attention to the DEC (for decimal) and Symbol columns.

http://www.ascii-code.com/

by your earlier post, consider using a loop, so you don't need a variable for each number.

http://java.sun.com/docs/books/tutorial/java/data/strings.html

[David Newton]

nathan gibson wrote:i am familiar with converting strings to numbers, but that is not what i am trying to do, im trying to see if there is another method because i have to up the number of trial to 1000 and that is way to many variable to make.

You said you were trying to add all the numbers in the string token--that implies converting each string representation of a number into a number and adding them. If the problem is something different, perhaps you could explain further. To get an average from the string tokens you just need to convert them to an integer in the loop you already have and add them, then divide, as you already stated.

[Ernest Friedman-Hill]

nathan gibson wrote: i have to up the number of trial to 1000 and that is way to many variable to make.

Are you familiar with the concept of an array, or a List?

[nathan gibson]

no im familiar with neither of these. we havent went over them yet.

[nathan gibson]

@ david. my question is though, will that work with something like a thousand trials. i was trying to find something that would basically work like average = sumToken / counter. if you think your way would be suitable would you please list an example of the code that i would need?

[David Newton]

It would work with a million trials: keep a sum, convert each token to an integer in the loop you already have, and add it to the sum. There's no need to create a new variable for each conversion--use the same one for the converted token, since you never need it again.