Gradebook Program - Calculate Averages Of 25 Students Using 2D Arrays
Apr 16, 2014
I am making a gradebook program that calculates the averages of 25 students using 2D arrays in which the students have four test grades. I have figured out how to display the averages of each student in one column but I cant seem to figure out how to display the letter grade of the average into another column.
Right now my program reads from a .txt doc
Heres what I've got.
TestGradeBook.java
import java.util.*;
import java.io.*;
public class TestGradeBook {
public static void main (String [] args ) throws IOException{
//Declarations
final int ROWS = 100;
final int TESTS = 4;
[Code] .....
GradeBook_Data.txt
Name100100100100
// basic name and grades
I have the program bellow that grades students(based on a two dimensional array with the answers) and i need to make it display the students based on the grades/scores in ascending order . I did that in two ways (using a array and a two dimensional array) but i have a hunch it can be done much more simple then i did it (but still using array object and nothing else ) .
public class GradeExam { /** Main method */ public static void main(String args[]) { // Students' answers to the questions char[][] answers = {
[code]....
My first solution creating an array with the grades for sorting :
public class C8_3 { public static void main(String args[]) { // Students' answers to the questions char[][] answers = { {'A', 'B', 'A', 'C', 'C', 'D', 'E', 'E', 'A', 'D'}, {'D', 'B', 'A', 'B', 'C', 'A', 'E', 'E', 'A', 'D'},
In this project each individual will create a data analysis program that will at a minimum,
1) read data in from a text file, 2) sort data in some way, 3) search the data in some way, 4) perform at least three mathematical manipulations of the data, 5) display results of the data analysis in numeric/textual form, and 6) display graphs of the data. In addition, 7) your program should handle invalid input appropriately and 8) your program should use some "new" feature that you have not been taught explicitly in class.
(Note: this is to give you practice learning new material on your own - a critical skill of today's programmer.) If you do not have a specific plan in mind for your project, below is a specific project that meets all of the qualifications as long as 7) and 8) are addressed in the implementation.
Everything is done except I need to call my methods in my GradeTester.
GradeBook:
/** *This class creates an array called scores. *This class determines the length of the array scores and determines the last grade in the array scores. *This class sorts the array using a bubble sort, and searches the array. *This class calculates the mean, standard deviation, and the median of the grades in the array scores. *Once the grades in the array is sorted, the class then calculates the highest and lowest grades in the array. */
public class GradeBook { public final int MAXARRAY_SZ = 20; double [] scores = new double [MAXARRAY_SZ]; int lastGrade = 0; double mean = 0;
i am fairly new to java but have made a few projects so i do know most aspects that would allow me to complete the task its just i have been stuck at the same place now for 2 days.The project is to create a java program that can read specific data within a csv file to work out the averages etc. The csv file is a database of different weather stats . an example of the first 12 months of the csv file is below..
I know that once the data is indexed i can than use a double to find the average of the 12 specific pieces of data and so on. once this is complete i should than be able to transfer the data to a simple graph.
I am still new to Java and have an assignment that I am stuck on. I believe I got the boolean function correct, however I cannot figure out what to write in the main function. I have exhausted searching, and trying different loops, arrays, etc.
As part of the instructions we are required to use loops and methods to solve to program this code. We are not allowed to use any set functions that are already built in java.The methods for intersection and difference MUST return int value.
import java.util.Scanner; public class setPractice { public static Scanner kbd; public static final int MAXSIZE = 20; public static void main(String[] args) { kbd = new Scanner(System.in);
How can I find the overall averages of the columns in this array?when i run my code it gives me an output that looks like this (showing me wrong averages): 0 1 2 3 overall grade
// GradeBook class uses switch statement to count A, B, C, D and F grades.
import java.util.Scanner; public class GradeBook { private String courseName; private int total; private int gradeCounter; private int aCount;
[Code] .....
Then eclipse told me that:
"Exception in thread "main" java.util.InputMismatchException at java.util.Scanner.throwFor(Unknown Source) at java.util.Scanner.next(Unknown Source) at java.util.Scanner.nextInt(Unknown Source) at java.util.Scanner.nextInt(Unknown Source) at chapter5_control_statements_II.GradeBook.inputGrades(GradeBook.java:52) at chapter5_control_statements_II.GradeBookTest.main(GradeBookTest.java:11)"
I`m trying to make a gradebook that uses random number generator to give the score, I also need to implement student numbers and sort everything with a total at the bottom. But I cant figure out how the bubblesorting works. This is my code so far:
package karakterbok; import static java.lang.Math; import java.util.Random; public class Karakterbok { public static void main(String[] args) { Random karakterer = new Random(); Random studid = new Random ();
A school has 100lockers and100 students. All lockers are closed on the first day of school. As the students enter, the first student, denoted S1, opens every locker. Then the second student, S2, begins with the second locker, denotedL2, and closes every other locker. Student S3beginswiththethirdlocker and changes every third locker (closes it if it was open, and opens it if it was closed). Student S4begins with locker L4 and changes every fourth locker. StudentS5 starts with L5andchanges every fifth locker, and soon,until student S100 changesL100.
After all the students have passed through the building and changed the lockers, which lockers are open?Write a program to find your answer. The program should display the answer like this:
Locker x is open Locker y is open... Locker z is open Design requirement: Use a method and an array of100 boolean elements,each of which indicates whether a locker is open (true) or closed (false). Initially,all lockers are closed.
I'm not sure why it's giving me errors in my code. I'll post it below.
1 2 public class Assignment5 { 3 4 public static void main(String[] args) { 5 //create array 6boolean locker[] = new boolean[100]; 7 //make them all closed 8for( int i = 0; i <= 99; i++){ 9locker[i]= false;
[Code] ....
I have errors in line 12 and 14 but not sure why or how to fix them.
I have an ArrayList filled with Student objects and all these students have a name. What I have to do is group these students in teams of 2 and make sure that 1. a student is not grouped with itself and 2. a student is not grouped twice.
The problem shows up when I iterate through the ArrayList and crosscheck a randomly generated number (for picking random students) with an ArrayList that contains already selected students, to make sure that we have no duplicates.
Here is my code:
public void generateTeams() { Iterator<Student> iteration = studentsArray.iterator(); while(iteration.hasNext()) { student1 = iteration.next(); // getRandomStudent returns a random Student object from the arraylist student2 = getRandomStudent();
[Code] .....
If I run it like this the program will freeze an take up a lot of CPU. This is probably because the final student has no other students left to pair with and will therefore keep randomly generating a number (the while loop in the middle). The list of students is 27 long so it has to work with an odd amount of students.
Any good way to crosscheck if the student has been picked before? I have tried emptying the original ArrayList before but that ends up with the same problem of there being no students to match with.
In the while loop I have edited out the part that causes it to generate random numbers infinitely. I do need to make sure the student hasn't been picked before though.
The purpose of this project is to determine the letter grade of students. The program needs to accept two command line arguments:
The first being the name of a disk file that contains the names of students, and their test scores, separated by commas followed by one or more spaces. Each line in the file will contain scores for one student.
The second argument is the name of an output disk file. The program is supposed to create a new output disk file using that name.
The number of students in the input file is unknown during compile time. The name of input and output files could be anything and only known during run time. Additionally, the average scores, along with the minimum and maximum scores for each test are to be displayed in the console.
Calculation: Final Score = quiz1 * .10 + quiz2 * .10 + quiz3 * .10 + quiz4 * .10 + midi * .20 + midii * .15 + final * .25 Final Score >= 90% then letter grade is A, 80%-89% B, 70%-79% C, 60-69% D, <= 59% F
Create an application that keeps track of students. The application should have 3 new classes.
1. Create a class which will represent an instance of 1 student:
I want to be able to display the user's name (Last, First), Age (in years as an integer) and GPA (to 2 decimal points). This class only needs a constructor and a toString method.
2. Create a Team class that will represent a group of students.
This class should allow the driver class to manage students for a given course. The class will keep track of the course name and section, the students in the class, and allow the driver to specify the max number of students to keep track of.
Methods: 1.Constructor 2.It should have a method to insert a single student into the array and return a Boolean indicating success or failure. 3.It should also have a method which returns a string with all of the course and student information formatted for display. You should make the name 12 characters long.
3. Create a driver class that will manage the whole process.
Pseudocode:
BEGIN Driver main method Initialize student count to 0 Input size of the array Instantiate a copy of the Team class Input a student name (or quit) WHILE (the student name is not quit) Input student age Input student GPA
how does the program know to calculate for only one year?
public class Interest2 { public static void main(String[] args) { double principal; // The value of the investment. double rate; // The annual interest rate. double interest; // The interest earned during the year.
I'm just learning about arrays. I have a small program to write that asks to create 2 arrays. One holding 5 names of flowers. One holding the prices of those 5 flowers. I ask the user what kind of flower they want and the quantity. I then need to create a loop that locates the flower name and uses that index to find the cost of the flower. I am struggling on how to write in code how to use one array index to find another. Example: Roses and $.50.
I am trying to figure out the Sieve of Eratosthenes program using arrays. I am trying to display the prime numbers of 1-100. My code right now is:
import java.text.DecimalFormat; import java.util.Scanner; public class TextLab06st { public static void main(String args[]) { // This main method needs additions for the 100 point version. Scanner input = new Scanner(System.in); System.out.println(" TextLab06
[code]...
I am getting the error <identifier? expected for the line "primes.[index] = false;"
I have spent the past 12 hours on it and have gotten no where. I need to create a program that will calculate different tax brackets. I have tried all combinations I can think of and can't get it to work!!! I am literally about to go insane! I need the program to calculate tax will be 1% for anything up to $50000. If the tax is over $50000, you keep that 1% of $50000 and then add the remaining. So for an income in the second range, it would be 1% of $50000, and then 2% of (income - $50000). This then continues for each range.
The problem I'm having is getting it to display the correct interest rates. I am not asking for you to write it for me. I want to learn. But at this point I have exhausted all resources available to me.
import java.util.Scanner; public class Project3taxinfo { public static void main(String[] args) { final double RATE1 = 0.01; //1% tax on the first $50,000 final double RATE2 = 0.02; //2% tax on the amount over $50,000 up to $75,000 final double RATE3 = 0.03; //3% tax on the amount over $75,000 up to $100,000 final double RATE4 = 0.04; //4% tax on the amount over $100,000 up to $250,000 final double RATE5 = 0.05; //5% tax on the amount over $250,000 up to $500,000 final double RATE6 = 0.06; //6% tax on the amount over $500,000
I'm starting with my version of very basic program: calculating area of circle. And of course it doesn't get well. My question: what is wrong in this code?
public class circleAre{ double radious; void putData(double radi){ radi = radious;
I am having a problem with my program. I can't get my program to calculate properly. Everything compiles and run but its just giving me a wrong answer. I am suposse to get 115.50 but instead I am getting .30...
order.java public class Order { double salesTaxRate; //initializing a variable for the sales tax rate. double subTotal; //initializing a varliable for the sub total. double shippingCost; //initializing a variable for shipping cost. double salesTax; //initializing a variable for sales tax. double totalCost; // initializing a variable for totale cost.
Assume the tanker is a cylinder of length 19.35 feet and volume 1320 gallons. What is the diameter in feet of the tanker truck? To solve this problem, write a Java program to calculate the diameter. For full credit, your Java application must follow these specifications.
1. The program must interactively input the capacity of the tanker in gallons and its length in feet. This should be done in the main method of your Tester class.
2. The input data should then be used to construct a TankerTruck object. You will need to write the TankerTruck class.
3. A TankerTruck method should be used by main to calculate the resulting diameter of the truck in feet.
4. Your program should use the standard Java constant for the math constant PI.
5. The output should be displayed using fixed-point notation, rounding to one decimal place of precision
import java.util.Scanner; public class SophiaKeyProgram1 { public static void main(String[] args) { // TODO Auto-generated method stub int numQuarter; //number of quarters in a year double rainfall=0; //the amount of rain
I am designing a program that generates 3 random numbers from 1-5 and if 2 match, the user wins $1. If 3 match, the user wins respectively:
All 1s - $5 2s - $10 3s - $25 4s - $50 5s - $100
I first used a loop to run until the user runs out of money or wishes to stop. Then I made 2 methods. 1 to generate the random numbers and 1 to see if the user won any money. I am storing the random numbers in an array called slotnumber.
This is what I have so far but I am getting compiling errors at while (cont == 'y') {
import java.util.Scanner; import java.util.Random; public class SlotMachine {
I am trying to create a program that reads a sentence, such as: "abba is running to the radar" scans this sentence, and then prints out all the palindromes. I am running into issues with my arrays and for statements. Here is my code:
static String palindrome, backwardsLower, palindromeLower, palindromeClean, backwards2, backwards = ""; static String[] words; static int counter; public static void main(String[] args) { palindrome = JOptionPane.showInputDialog("Please enter a phrase. " +
[Code] ...
I am aware that there is a few "useless" variables in there at the moment, I will clean them up (as well as some useless statements, I see those too). The issue comes at about line 17. The variable backwards REMOVES all the spaces from the array, so when it comes time to compare the strings, it is comparing individual words to the ENTIRE string, thus no words will ever be a palindrome.
Write method distance, which calculates the distance between two points (x1, y1) and (x2, y2). All numbers and returned values should be of type double. Incorporate this method into an program that enable the user to enter the coordinates of the points, then calculate and display the distance by calling the method –distance.
I've tried numerous times to make it work and I'm on the right path, however I'm missing some things in the code to make my results look like this later on, which I've attached onto this post.
write a program that calculates the change due to a customer by denomination; that is, how many pennies, nickels, dimes, etc. are needed in change. The input is to be purchase price and the size of the bill tendered by the customer($100, $50, $20, $10, $5, $1).
