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Read Scores from text file and sort into array

Im trying to get my test score program to work. Whenever I type in the pathfile to read from the text file the program would read 4 out of the 5 numbers that are there.Also, no matter what number there are it is always going to display my minimum as 0 when it is not true. Any help is truly appreciated!
import java.io.File;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.util.Arrays;
import java.util.Scanner;
public class Exam{
public static void main(String[] args) throws IOException {
System.out.println("Welcome!" + "\n");
//File location
System.out.println("Where is the data file:");
Scanner userInput = new Scanner(System.in);
String userFile = userInput.nextLine();
int i = 0;
int scores[] = readScores(userFile);
System.out.println("Minimum score: " + scores[0]);
System.out.println("Maximum score: " + scores[(scores.length - 1)]);
//Average Calculation
double gradesTotal = 0;
for (i=0; i<scores.length; ++i){
gradesTotal = gradesTotal + scores[i];
}
double mean = gradesTotal/scores.length;
System.out.println("Average score: " + mean);
//Mean Calculation
double median;
if (scores.length % 2 == 0)
median = ((scores[(scores.length/2) - 1]) + scores[(scores.length/2)]) / 2;
else
median = scores[(scores.length/2)];
System.out.println("Median score: " + median + "\n");
//Number of Grades
int gradeA = 0;
int gradeB = 0;
int gradeC = 0;
int gradeD = 0;
int gradeF = 0;
for (i=0; i<scores.length; i++)
{
if (scores[i] >= 90 && scores[i] <=100){
gradeA++;
}
else if (scores[i] <= 89 && scores[i] >=80){
gradeB++;
}
else if (scores[i] <= 79 && scores[i] >=70){
gradeC++;
}
else if (scores[i] <= 69 && scores[i] >=60){
gradeD++;
}
else if (scores[i] <= 59 && scores[i] >=1){
gradeF++;
}
}
System.out.println("Scores by letter grade: ");
System.out.println("A: " + gradeA);
System.out.println("B: " + gradeB);
System.out.println("C: " + gradeC);
System.out.println("D: " + gradeD);
System.out.println("F: " + gradeF);
}
//Reads the data from the submitted file
private static int[] readScores(String userFile) throws FileNotFoundException
{
File inputFile = new File(userFile);
Scanner stats = new Scanner(inputFile);
try {
int scores[] = new int[stats.nextInt()];
int i = 0;
while (stats.hasNext()){
scores[i] = stats.nextInt();
i++;
}
System.out.println("\n" + "There are " + (i) + " scores" + "\n");
Arrays.sort(scores);
return scores;
}
finally {
stats.close();
}
}
}
Text file:
72
31
13
39
74
Program output:
There are 4 scores
Minimum score: 0
Maximum score: 74
Average score: 2.1805555555555554
Median score: 0.0
Number of scores by letter grade:
A: 0
B: 0
C: 1
D: 0
F: 3

int scores[] = new int[stats.nextInt()];
here you take the first of your values and then you dont have it where you need it.
That is probably also the reason why your calculations are so messed up. you create an array of lenght 72 and use that lenght for the number of values.
Maybe you want to use a list instead. It allows you to add as many values as you want without specifying a number like you have to do when you use an array.

How to print proper minimum and maximum from user input

I am trying to write a program that allows a user to enter in a number of random grades they want to display along with the sum, average, minimum and maximum of the generated list. The grades range from 60 - 100.
The program is printing the min properly and the sum is adding up the previously generated sum along with the newly generated one. How can I change it so that it give the correct output for the minimum and so that is stops adding the previou sum to the new one? Any help would be appreciated.
The image link for the output shows the minimum output issue. The min should be 66.0 but it says 59.0.
output
import java.util.Scanner;
public class A03C
{
public static void main(String[] args)
{
Scanner input = new Scanner(System.in);
System.out.print("How many scores? ");
int howMany = input.nextInt();
double score = 0;
double sum = 0;
double average = 0;
double max = 0;
double min = 60;
while (howMany > 0)
{
for (int i = 1; i <= howMany; i++)
{
score = 60 + (int)(Math.random() * ((100 - 60) +1));
if (letterGrade(score));
sum += score++;
average = (sum/howMany);
if (score > max)
max = score;
if (score < max)
min = score;
}
System.out.println("Sum: " + sum);
System.out.println("Average: " + average);
System.out.println("Max: " + (max - 1));
System.out.println("Min: " + (min - 1));
System.out.println("How many scores? ");
howMany = input.nextInt();
}
}
public static boolean letterGrade(double score)
{
if (score >= 92.0)
System.out.println(score + " is an A");
else if (score >= 83.0)
System.out.println(score + " is a B");
else if (score >= 75.0)
System.out.println(score + " is a C");
else
System.out.println(score + " is an F");
return false;
}
}

Just clean the sum variable after the execution, also I changed the return of the letterGrade to true:
import java.util.Scanner;
public class A03C {
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
System.out.print("How many scores? ");
int howMany = input.nextInt();
double score = 0;
double sum = 0;
double average = 0;
double max = 0;
double min = 60;
while (howMany > 0) {
for (int i = 1; i <= howMany; i++) {
score = 60 + (int) (Math.random() * ((100 - 60) + 1));
if (letterGrade(score))
sum += score++;
average = (sum / howMany);
if (score > max)
max = score;
if (score < max)
min = score;
}
System.out.println("Sum: " + sum);
System.out.println("Average: " + average);
System.out.println("Max: " + (max - 1));
System.out.println("Min: " + (min - 1));
System.out.println("How many scores? ");
sum = 0;
howMany = input.nextInt();
}
}
public static boolean letterGrade(double score) {
if (score >= 92.0)
System.out.println(score + " is an A");
else if (score >= 83.0)
System.out.println(score + " is a B");
else if (score >= 75.0)
System.out.println(score + " is a C");
else
System.out.println(score + " is an F");
return true;
}
}

Before continue, i definitely think that you should read #joe C comment.
As i understand you are a beginner, i will explain the changes i did.
import java.util.Scanner;
public class A03C
{
public static void main(String[] args)
{
Scanner input = new Scanner(System.in);
System.out.print("How many scores? ");
int howMany = = input.nextInt();
double score = 0;
double sum = 0;
double average = 0;
double max = 60;
double min = 100;
while (howMany > 0)
{
for (int i = 1; i <= howMany; i++)
{
score = 60 + (int)(Math.random() * ((100 - 60) +1));
letterGrade(score);
sum += score++;
average = (sum/howMany);
if (score > max)
max = score;
if (score < min)
min = score;
}
System.out.println("Sum: " + sum);
System.out.println("Average: " + average);
System.out.println("Max: " + (max - 1));
System.out.println("Min: " + (min - 1));
System.out.println("How many scores? ");
howMany = input.nextInt();
}
}
public static void letterGrade(double score)
{
if (score >= 92.0)
System.out.println(score + " is an A");
else if (score >= 83.0)
System.out.println(score + " is a B");
else if (score >= 75.0)
System.out.println(score + " is a C");
else
System.out.println(score + " is an F");
}
}
Starting with the function letterGrade. Since the function always return false and just prints a sentence, you can replace boolean to void.
Another mistake you did was that if you want to find max and min, the variables shall take the inverse of you want. So the variable max shall take the minimum variable (60) and the maximum value (100).
Finally, in order to change variables max and min you must compare the new value to their current value. This is, to change min value, for example, you have to compare score with current min.
Hope it helps.

Java GPA Program Issue

My program for some reason is calculating the GPA average wrong. If I enter 4.0 three times, then it says the average GPA is 3.0 but should be 4.0. Can someone help me find the issue?
//variables
double gpa = 0;
double total = 0;
int counter = 0;
int counter2 = 0;
do
{
String gpaEntry = JOptionPane.showInputDialog("Please enter GPAs:");
gpa = Double.parseDouble(gpaEntry);
if (gpa >= 3.5)
counter2 ++;
total += gpa;
counter ++;
}
while (gpa != 0);
double average = (double) (total/counter);
JOptionPane.showMessageDialog(null, "The Average GPA is: " + average);
JOptionPane.showMessageDialog(null, "Number of students:" + counter2);

Let's walk through the code
gpa = 0
get user input (user enters '2')
now gpa = 2
total += 2
counter ++
while(gpa != 0) // nope, gpa is 2
loop back
get user input (user enters '0')
now gpa = 0
total += 0
counter ++ // oops!
while(gpa != 0) // yep, quit the loop
but it's too late, we already incremented counter, so our average calculation is wrong

What is wrong is that if a user enters 0, then it runs the program and then exits.
Try this code (Sorry, I do not have an editor at the moment so you might have to fix some small thing).
//variables
double gpa = 0;
double total = 0;
int counter = 0;
int counter2 = 0;
String gpaEntry = JOptionPane.showInputDialog("Please enter GPAs:");
gpa = Double.parseDouble(gpaEntry);
while (gpa != 0) {
if (gpa >= 3.5)
counter2 ++;
total += gpa;
counter ++;
gpaEntry = JOptionPane.showInputDialog("Please enter GPAs:");
gpa = Double.parseDouble(gpaEntry);
}
JOptionPane.showMessageDialog(null, "The Average GPA is: " + average);
JOptionPane.showMessageDialog(null, "Number of students:" + counter2);
Comment if you have any more questions.

Java-Number of scores needs to be one less in answer

So here is my code:
package e7;
import java.util.Scanner;
public class Q1 {
public static void main(String[] args)
{
double[] scores = new double[10];
double sum = 0.0D;
int count = 0;
Scanner sc = new Scanner(System.in);
do {
System.out.print("Enter a new score (-1 to end): ");
scores[count] = sc.nextDouble();
if (scores[count] >= 0.0D)
sum += scores[count];
}
while (scores[(count++)] >= 0.0D);
System.out.println("The total number of scores is: " + count );
double average = sum / (count - 1);
int numOfAbove = 0;
int numOfBelow = 0;
for (int i = 0; i < count - 1; i++) {
if (scores[i] >= average)
numOfAbove++;
else
numOfBelow++;
}
System.out.printf("Average is " + "%.2f\n",average);
System.out.println("Number of scores above or equal to the average " + numOfAbove);
System.out.println("Number of scores below the average " + numOfBelow);
}
}
How do make it display the correct number of scores calculated? If I input 2 numbers and then do the -1 one to end it keeps saying 3 scores. Should only be two. How do I fix this? Thanks

System.out.println("The total number of scores is: " + count );
You probably want:
System.out.println("The total number of scores is: " + (count - 1));

You could also change your loop from a do while to a while loop as follows,
while (true) {
System.out.print("Enter a new score (-1 to end): ");
double tempDouble = sc.nextDouble();
if (tempDouble >= 0.0D)
scores[count] = tempDouble;
sum += scores[count];
count++;
else
break;
}
That way as if your double input isn't correct it would break out of the while loop when the user entered -1. You might have to tweak it a bit for your use case.

Beginner java programming if-else statements inefficient code

My code is correct but it looks too big.I was wondering if it could be more efficient and with even fewer variables.Do you have any hints?Thanks
sample output
Enter three scores: 87 42 94
The lowest score was: 42
The average without the lowest score is: 90.5
The grade is: A
<code>
import java.util.Scanner;
public class GradeAverager
{
public static void main(String[] args)
{
int score1,score2,score3;
double average,average_no_lowest;
Scanner keyboard = new Scanner(System.in);
System.out.print("Enter three scores: ");
score1 = keyboard.nextInt();
score2 = keyboard.nextInt();
score3 = keyboard.nextInt();
average = (score1 + score2 + score3) / 3.0;
System.out.println();
System.out.println("The average is: " + average);
if (score1 < score2 && score1 < score3)
System.out.println("The lowest score was:" + score1);
else if (score2 < score1 && score2 < score3)
System.out.println("The lowest score was:" + score2);
else if (score3 < score1 && score3 < score2)
System.out.println("The lowest score was:" + score3);
if (score1 < score2 && score1 < score3){
average_no_lowest = (score2 + score3)/2.0;
System.out.println("The average without the lowest score is: " + average_no_lowest);
if(average_no_lowest > 90)
System.out.print('A');
else if(average_no_lowest < 90 && average_no_lowest > 80 )
System.out.print('B');
else if(average_no_lowest > 70 && average_no_lowest < 80)
System.out.print('C');
else
System.out.print('D');
}
else if (score2 < score1 && score2 < score3){
average_no_lowest = (score1 + score3)/2.0;
System.out.println("The average without the lowest score is: " + average_no_lowest);
if(average_no_lowest > 90)
System.out.print('A');
else if(average_no_lowest < 90 && average_no_lowest > 80 )
System.out.print('B');
else if(average_no_lowest > 70 && average_no_lowest < 80)
System.out.print('C');
else
System.out.print('D');
}
else if (score3 < score1 && score3 < score2){
average_no_lowest =(score1 + score3)/2.0;
System.out.println("The average without the lowest score is: " + (score1 + score3)/2.0);
if(average_no_lowest > 90)
System.out.print('A');
else if(average_no_lowest < 90 && average_no_lowest > 80 )
System.out.print('B');
else if(average_no_lowest > 70 && average_no_lowest < 80)
System.out.print('C');
else
System.out.print('D');
}
}
}
</code>

Your section of code which reads
if(average_no_lowest > 90)
System.out.print('A');
else if(average_no_lowest < 90 && average_no_lowest > 80 )
System.out.print('B');
else if(average_no_lowest > 70 && average_no_lowest < 80)
System.out.print('C');
else
System.out.print('D');
}
is duplicated 3 times. Put it into a method.
Don't be worried about performance until it is a proven problem. Be worried about how easy it is to read and maintain the code.
Code has 2 audiences - the compiler and humans. Humans matter more than compilers.

Store the lowest score in a variable e.g. lowest_score.
and do the average by (total - lowest_score) / 2
It is the most efficient

You can use the following code,these have fewer lines of code and gives the same output as you want::
public static void main(String[] args) {
int score1, score2, score3, status;
double average, average_no_lowest;
Scanner keyboard = new Scanner(System.in);
System.out.print("Enter three scores: ");
score1 = keyboard.nextInt();
score2 = keyboard.nextInt();
score3 = keyboard.nextInt();
average = (score1 + score2 + score3) / 3;
System.out.println("Average Score was:: " + average);
if (score1 < score2 && score1 < score3) {
status = 1;
System.out.println("The lowest score was:: " + score1);
} else if (score2 < score1 && score2 < score3) {
status = 2;
System.out.println("The lowest score was:: " + score2);
} else {
status = 3;
System.out.println("The lowest score was:: " + score3);
}
if (status == 1) {
average_no_lowest = (score2 + score3) / 2;
System.out.println("The average without the lowest score is: "
+ average_no_lowest);
} else if (status == 2) {
average_no_lowest = (score1 + score3) / 2;
System.out.println("The average without the lowest score is: "
+ average_no_lowest);
} else {
average_no_lowest = (score1 + score2) / 2;
System.out.println("The average without the lowest score is: "
+ average_no_lowest);
}
}