Question

please write the code in java so it can run on jGRASP import java.util.Scanner;

  2 import java.io.*; //This imports input and output (io)
classes that we use

  3                   //to read and write to files. The * is the
wildcard that will

  4                   //make all of the io classes available if
I need them

  5                   //It saves me from having to import each
io class separately.

6 /**

7.   7     This program reads numbers from a file, calculates the
   

8.   8     mean (average) and standard deviation, and writes the
   

results
  9    to a file.

 10 */
 11
 12 public class StatsDemo
 13 {
 14    public static void main(String[] args) throws IOException
 15    {
 16       //the throws IOException means that if we are unable

to read from or write
 17       //to our files, we need to throw an exception which

means the program can
 18       //not continue until we fix the problem causing the

exception to throw.

19

20.  20        double sum = 0;
    

21.  21        int count = 0;
    

22.  22        double mean = 0;
    

23.  23        double stdDev = 0;
    

//The sum of the numbers
//The count of numbers added
//The average of the numbers
//The standard deviation - a

measure of how widely dispersed the numbers are

24.  24        String line;         //To hold a line from the file
    

25.  25        double difference = 0;  //The value and mean
    

difference
 26       String filename;     //Store the name of the file that

is being read

 27
 28       Scanner keyboard = new Scanner (System.in);
 29

30.  30        //Prompt the user and read in the file name
    

31.  31        System.out.println("This program calculates statistics
    

on a file containing numbers.");
 32       System.out.println("Enter the file name: ");

 33       filename = keyboard.nextLine();
 34

35.  35        FileReader freader = new FileReader(filename);
    

36.  36        //FileReader is meant for reading streams of
    

characters from a file
 37       //For reading streams of raw bytes, use

FileInputStream

38

39.  39        BufferedReader input = new BufferedReader(freader);
    

40.  40        //Creates a BufferedReader object passing it to the
    

FileReader object
 41       //Java.io.BufferedReader class reads from a character-

input stream
 42       //buffering characters so as to provide for the

efficient reading
 43       //of a sequence of characters
 44

45.  45        //Priming read to read the first line of the file
    

46.  46        line = input.readLine();   //readLine is a method to
    

read a line of text.

 47       System.out.println("Printing the line just read to the
monitor " + line);

48

 49       //Loop continues reading the Numbers.txt until it hits
the end of the file

 50       //This loop is summing the numbers as it reads them in
so that we can calc. the mean/avg

 51       //This loop is counting how many numbers it has read
in from the file

 52       while (line != null) //null is nothing. We are reading
until we find nothing

53 {

54.  54           //convert the line into a double value
    

55.  55           //add the value to the sum.
    

56.  56           sum = sum + Double.parseDouble(line);
    

57

58.  58           //Increment the counter
    

59.  59           count++; //count = count + 1
    

60

61.  61           line = input.readLine();
    

62.  62           System.out.println("Printing the line just read to
    

the monitor " + line);
 63       }
 64

65.  65        //Close the input file
    

66.  66        input.close();
    

67

68.  68        //Store the calculated mean
    

69.  69        mean = sum / count;
    

70

 71       //Reconnect to the FileReader object passing the
filename

 72       freader = new FileReader(filename);
 73

74.  74        //Reconnect to the BufferedReader object passing it
    

75.  75        //the FileReader object
    

76.  76        input = new BufferedReader(freader);
    

77

78.  78        sum = 0; //Reinitialize the sum
    

79.  79        count = 0 ; //Reinitialize the count
    

80

81.  81        //Priming read to read the first line of the file
    

82.  82        line = input.readLine();   //readLine is a method to
    

read a line of text.

 83       System.out.println("Printing the line just read to the
monitor " + line);

84

 85       while (line != null) //null is nothing. We are reading
until we find nothing

86 {

87.  87           //convert the line into a double
    

88.  88           difference = Double.parseDouble(line) - mean;
    

89

90.  90           //Add the square of the difference to the mean
    

91.  91           sum = sum + Math.pow(difference, 2);
    

92

93.  93           //Increment the counter
    

94.  94           count++; //count = count + 1
    

 95
 96          line = input.readLine();   //readLine is a method

to read a line of text.

 97          System.out.println("Printing the line just read to
the monitor " + line);

98

 99       } //end of 2nd while loop
100

101. 101        //Close the input file
     

102. 102        input.close();
     

103

104. 104        //Store the calculated standard deviation
     

105. 105        stdDev = Math.sqrt(sum / count);
     

106
107       //Create the object of type FileWriter using
MyResults.txt
108       FileWriter fwriter = new FileWriter("MyResults.txt");
109
110       //Create an object of PrintWriter passing it to the
FileWriter object
111       PrintWriter output = new PrintWriter(fwriter);
112

113. 113        //Print the results to the output file
     

114. 114        output.printf("mean = %.3f\r\n", mean);
     

115. 115        output.printf("standard deviation = %.3f", stdDev);
     

116

117. 117        //close the output file
     

118. 118        output.close();
     

119
120   }// end of main
121 } //end of class
122
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Answer 1

Code:

package assignment;

import java.io.BufferedReader;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.Scanner;

public class Count {

   public static void main(String[] args) throws IOException {

       double sum = 0;
       int count = 0;
       double mean = 0;
       double stdDev = 0;
       //The sum of the numbers
       //The count of numbers added
       //The average of the numbers
       //The standard deviation - a
       String line=null; //To hold a line from the file
       double difference = 0; //The value and mean difference
       String filename="location path of the file"; //Store the name of the file that is being read
       Scanner keyboard = new Scanner (System.in);
         
       //Prompt the user and read in the file name
       System.out.println("This program calculates statistics on a file containing numbers.");
       System.out.println("Enter the file name: ");
       filename = keyboard.nextLine();
         
       FileReader freader = new FileReader(filename);
       //FileReader is meant for reading streams of characters from a file
       //For reading streams of raw bytes, useFileInputStream
      

       BufferedReader input = new BufferedReader(freader);
       //Creates a BufferedReader object passing it to the FileReader object
       //Java.io.BufferedReader class reads from a character input stream
       //buffering characters so as to provide for the efficient reading
       //of a sequence of characters
         
       //Priming read to read the first line of the file
       line = input.readLine(); //readLine is a method to read a line of text.
       System.out.println("Printing the line just read to the monitor " + line);
       //Loop continues reading the Numbers.txt until it hits the end of the file
       //This loop is summing the numbers as it reads them in so that we can calc. the mean/avg
       //This loop is counting how many numbers it has read in from the file
       while (line != null) //null is nothing. We are reading until we find nothing
       {

       //convert the line into a double value
       //add the value to the sum.
       sum = sum + Double.parseDouble(line);
       //Increment the counter
       count++; //count = count + 1
       line = input.readLine();
       System.out.println("Printing the line just read to the monitor " + line);
      
       }
       System.out.println("sum: "+sum);
       System.out.println("count: "+count);
         
       //Close the input file
       input.close();
      

       //Store the calculated mean
       mean = sum / count;
      

       //Reconnect to the FileReader object passing the filename
       freader = new FileReader(filename);
         
       //Reconnect to the BufferedReader object passing it
       //the FileReader object
       input = new BufferedReader(freader);
      

       sum = 0; //Reinitialize the sum
       count = 0 ; //Reinitialize the count
      

       //Priming read to read the first line of the file
       line = input.readLine(); //readLine is a method to read a line of text.
       System.out.println("Printing the line just read to the monitor " + line);
      

       while (line != null) //null is nothing. We are reading until we find nothing
       {

       //convert the line into a double
       difference = Double.parseDouble(line) - mean;
      

       //Add the square of the difference to the mean
       sum = sum + Math.pow(difference, 2);
       //Increment the counter
       count++; //count = count + 1
         
       line = input.readLine(); //readLine is a method to read a line of text.
       System.out.println("Printing the line just read to the monitor " + line);
      

       } //end of 2nd while loop
      
       //Close the input file
       input.close();
      

       //Store the calculated standard deviation
       stdDev = Math.sqrt(sum / count);
      
       //Create the object of type FileWriter using MyResults.txt
       FileWriter fwriter = new FileWriter("Numbers.txt");
      
       //Create an object of PrintWriter passing it to the FileWriter object
       PrintWriter output = new PrintWriter(fwriter);
      
       //Print the results to the output file
       output.printf("mean = %.3f\r\n", mean);
       output.printf("standard deviation = %.3f", stdDev);
      

       //close the output file
       output.close();
       }// end of main
}//end of class

Note:***I hope your happy with my answer***If you have any doubts please comment me*****Thank you........