CODEWITHSUNDEEP
javaarrays
Minnie21
Minnie21

Reputation: 29

reading grades from file

I am having trouble figuring out what the problem is with my coding. It needs to read text from a file and print the avg, max, and min.

import java.util.*;
import java.io.*;

public class LoopAndHalf{
   public static void main(String[]args)throws FileNotFoundException{
     Scanner input = new Scanner(new File("midterm.txt"));
     int lineNo=0;
     int id=0;
     int grade =0;
     String name;

     int min=1000;
     int max=-1000;
     int sum=0;
     int count=0;

     int[] scale = new int[6];

   while(input.hasNextLine()){
        input.nextLine();
        lineNo++;

     Scanner lineScan = new Scanner(line);
     id = lineScan.nextInt();
     name = lineScan.next();
     grade = lineScan.nextInt();
     count++;    
     if(grade>max){
      max=grade;
     }
     if(grade<min){
      min=grade;
     }    
     if(grade>=96){
      scale[5]++;
     }else if(grade>=91){
      scale[4]++;
     }else if(grade>=86){
      scale[3]++;
     }else if(grade>=81){
      scale[2]++;
     }else if(grade>=76){
      scale[1]++;
     }else{
      scale[0]++;
     }    
  }//end while loop

System.out.println("Scale array: " + Arrays.toString(scale));
System.out.println("Count: " + count);    
double avg= (double) sum/count;
System.out.println("Min: " + min);
System.out.println("Max: " + max);
System.out.println("Avg: " + avg);

//draw histogram
System.out.println();    
for(int i=0; i<scale.length; i++){      
  if(i==0){
    System.out.println("   - 75: ");
  }else if(i==1){
    System.out.println("76 - 80: ");
  }else if(i==2){
    System.out.println("81 - 85: ");
  }else if(i==3){
    System.out.println("86 - 90: ");
  }else if(i==4){
    System.out.println("91 - 95: ");
  }else{
    System.out.println("95 + : ");
  }     
}//end for loop

int[] counts = new int[101];     // counters of test scores 0 - 100        
    while (input.hasNextInt()) {     // read file into counts array
        int score = input.nextInt();
        counts[score]++;             // if score is 87, then counts[87]++
    }        
    for (int i = 0; i < counts.length; i++) {    // print star histogram
        if (counts[i] > 0) {
            System.out.print(i + ": ");
            for (int j = 0; j < counts[i]; j++) {
                System.out.print("*");
            }
            System.out.println();
        }
    }

   }//end main
  }//end class

The line that keeps giving me trouble is

Scanner lineScan = new Scanner(line);

the error is telling me that line cannot be resolved to a variable, but that is the only thing that is causing me problems. Any pointers would be appreciated. Thanks

Upvotes: 0

Views: 472

Answers (2)

Bill the Lizard
Bill the Lizard

Reputation: 405955

You're reading a line of input, but you're not saving it in a variable. Change

input.nextLine();

to

String line = input.nextLine();

Upvotes: 3

Moonhead
Moonhead

Reputation: 1568

This is probably what you want to achieve. Java has a builtin BufferReader.IO

BufferedReader reader = new BufferedReader(new FileReader("midterm.txt"));
String line = null;
while ((line = reader.readLine()) != null) {
   // Do what you want
}

Upvotes: 2

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