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Help with a test score problem

Ive been trying to write a program that will ask for 5 test scores, give you the average of the scores and also the corresponding grade that goes with them, unfortunately the grade doesn't seem to post when called. Any help would be welcome.

Code:

import javax.swing.JOptionPane; //Needed for GUI

import java.text.DecimalFormat; //needed to format the Output





public class avg_Score_Anderson

{//Begin class

        public static void main(String[] args)

        {//Begin main method



                String inputString;   //For reader's input

                double Score1,       //Define score1

                           Score2,      //Define  score2

                            Score3,     //Define   score3

                              Score4,    //Define    score4

                            Score5,   //Define     score5

                       Average ;//Define      Average



DecimalFormat formatter = new DecimalFormat("#,##0.0"); //format the scores



                // Get the five scores

                inputString=

                  JOptionPane.showInputDialog("Enter the First Test Score: "); //ask user to enter the first test score

                Score1 = Double.parseDouble(inputString);



                inputString=

                  JOptionPane.showInputDialog("Enter the Second Test Score: ");//ask user to enter the second test score

                Score2 = Double.parseDouble(inputString);



                inputString=

                  JOptionPane.showInputDialog("Enter the third test score: ");//ask user to enter the third test score

                Score3 = Double.parseDouble(inputString);



                inputString=

                  JOptionPane.showInputDialog("Enter the fourth test score: ");//ask user to enter the fourth test score

                Score4 = Double.parseDouble(inputString);



                inputString=

                  JOptionPane.showInputDialog("Enter the fifth test score: ");//ask user to enter the fifth test score

                Score5 = Double.parseDouble(inputString);



            // Call to method calcAverage and output the 5 test average

          Average = calcAverage(Score1, Score2, Score3, Score4, Score5);







                // Display Average test Score and Determine the letter grade for each test and call to determineGrade



                                JOptionPane.showMessageDialog(null, "\t\nTest score one is : " +formatter.format(Score1)  +"\t Grade: " + determineGrade(Score1)

                                                                  + "\t\nTest score two is : " +formatter.format(Score2)  +"\t Grade: " + determineGrade(Score2)

                                                                  + "\t\nTest score three is : " +formatter.format(Score3)  +"\t Grade: " + determineGrade(Score3)

                                                                  + "\t\nTest score four is : " +formatter.format(Score4)  +"\t Grade: " + determineGrade(Score4)

                                                                  + "\t\nTest score five is : " +formatter.format(Score5)  +"\t Grade: " + determineGrade(Score5)

                                                                  + "\n"

                                                                  + "\t\nYour average test score is : " +formatter.format(Average) +"\t Grade: " + determineGrade(Average),

                                                            "\tYour Test Results",JOptionPane.INFORMATION_MESSAGE);



                }//end Main method



                // Calculate the average of the five test scores

                public static double calcAverage(double Score1, double Score2, double Score3, double Score4, double Score5)

                {

                        double Average = ((Score1 + Score2 + Score3 + Score4 + Score5) / 5);

                        return Average;

                }



                // Determine the letter grade for the average and 5 test scores

                public static double determineGrade(double Average)

                {

                        char grade; // Define grade



                        // Determine letter grade

                        if (Average>=90)

                        {

                                grade = 'A';

                        }

                        else if (Average>=80)

                        {

                                grade = 'B';

                        }

                        else if (Average>=70)

                        {

                                grade = 'C';

                        }

                        else if (Average>=60)

                        {

                                grade = 'D';

                        }

                        else if (Average<60)

                        {

                                grade = 'F';

                        }

                        else

                        {

                                JOptionPane.showMessageDialog(null, "error\n");

                        }



                        return grade;



                }//end determinegrade method

}//end class

are any of the grades posting? have you set break points to step through? i read through and nothing stands out as wrong- are there any exceptions? is the double grade displaying and just the char is not?

the only error is

C:\Desktop\avg_Score_Anderson.java:97: error: variable grade might not have been initialized
return grade;
^
1 error

The only thing that does not post is the letter grade, the actual number grades and average of them all post correctly.

Im not sure if the char is incorrect or if i just skipped a step with the public static double determineGrade(double Average) part of the code.

Thanks again for any help.

I am surprised it is letting you compile- I found it; errors out in C# :P
you function "determineGrade" is a double- yet you are expecting it to be a char, and you are trying to return a char- you can't implicitly convert a char to a double.

also the variable grade is not necessarily getting initialized- well it is (as it is the end result of a set of if/elseif statements) but in C# anyways it doesn't know that for sure- I was able to modify it by changing all those if/elseif's to a switch and default returning 'E' for error. this also then eliminates the need for the variable grade- or you could set grade to a variable and then return it but it is redundant...

Code:

char grade;

.....

grade = 'E';

return grade;

.... same as ....

return 'E';

in short- I would make the set of if's be a switch (you will need to change up your logic a little bit) and the bottom line issue is you are trying to on-the-fly convert a char to a double.

ended up just removing the last else option and making it the letter F, and also changing the base of that statement to a char and seems to run perfect now.

Finished code for anyone interested and thanks for all the help.

Code:

import javax.swing.JOptionPane; //Needed for GUI

import java.text.DecimalFormat; //needed to format the Output





public class avg_Score_Anderson

{//Begin class

        public static void main(String[] args)

        {//Begin main method



                String inputString;   //For reader's input

                double Score1,       //Define score1

                           Score2,      //Define  score2

                            Score3,     //Define   score3

                              Score4,    //Define    score4

                            Score5,   //Define     score5

                       Average ;//Define      Average



DecimalFormat formatter = new DecimalFormat("#,##0.0"); //format the scores



                // Get the five scores

                inputString=

                  JOptionPane.showInputDialog("Enter the First Test Score: "); //ask user to enter the first test score

                Score1 = Double.parseDouble(inputString);



                inputString=

                  JOptionPane.showInputDialog("Enter the Second Test Score: ");//ask user to enter the second test score

                Score2 = Double.parseDouble(inputString);



                inputString=

                  JOptionPane.showInputDialog("Enter the third test score: ");//ask user to enter the third test score

                Score3 = Double.parseDouble(inputString);



                inputString=

                  JOptionPane.showInputDialog("Enter the fourth test score: ");//ask user to enter the fourth test score

                Score4 = Double.parseDouble(inputString);



                inputString=

                  JOptionPane.showInputDialog("Enter the fifth test score: ");//ask user to enter the fifth test score

                Score5 = Double.parseDouble(inputString);



            // Call to method calcAverage and output the 5 test average

          Average = calcAverage(Score1, Score2, Score3, Score4, Score5);







                // Display Average test Score and Determine the letter grade for each test and call to determineGrade







                                JOptionPane.showMessageDialog(null, "Test score                  Grade "

                                                                                                  + "\n----------------------------------"

                                                                                                  + "\n" +formatter.format(Score1) + "                                  " + determineGrade(Score1)

                                                                                                  + "\n" +formatter.format(Score2) + "                                  " + determineGrade(Score2)

                                                                                                  + "\n" +formatter.format(Score3) + "                                  " + determineGrade(Score3)

                                                                                                  + "\n" +formatter.format(Score4) + "                                  " + determineGrade(Score4)

                                                                                                  + "\n" +formatter.format(Score5) + "                                  " + determineGrade(Score5)

                                                                                                  + "\n\n"

                                                                                                  + "Your average test score is : \n" +formatter.format(Average) + "                                  "

                                                                                                  + determineGrade(Average));







                }//end Main method



                // Calculate the average of the five test scores

                public static double calcAverage(double Score1, double Score2, double Score3, double Score4, double Score5)

                {

                        double Average = ((Score1 + Score2 + Score3 + Score4 + Score5) / 5);

                        return Average;

                }



                // Determine the letter grade for the average and 5 test scores

                public static char determineGrade(double Average)

                {

                        char grade; // Define grade



                        // Determine letter grade

                        if (Average>=90)

                        {

                                grade = 'A';

                        }

                        else if (Average>=80)

                        {

                                grade = 'B';

                        }

                        else if (Average>=70)

                        {

                                grade = 'C';

                        }

                        else if (Average>=60)

                        {

                                grade = 'D';

                        }

                        else

                        {

                                grade = 'F';

                        }





                        return grade;



                }//end determinegrade method

}//end class