Code isn't giving me the output that I want and keeps giving me NaN
What I want -
Enter the A value for the line: 2.45
Enter the B value for the line: 4
Enter the C value for the line: -8
Enter the x coordinate of the point: 2.17
Enter the y coordinate of the point: -4
Distance from the point to the line is: 3.9831092774319026
What I am getting
Distance from the point to the line is: NaN
Here is my code-
Tester-
import java.io.*;
import java.util.*;
class tester
{
public static double A;
public static double B;
public static double C;
public static double distance;
public static void main(String args[])
Am new to programming and am trying to create a system that is similar to a train timetable system.I want the user to be able to enter the stops between two stations ( from a preset list of 5 stations ) and this be saved as an array list, and this array list be saved accordingly within a 2D array so if they were to look in [1][2] there would be an arraylist of stops between station 1 and 2.I used this to initialise the array of arraylists (in a class i created called stops)
public void stops(){ for (int i = 0; i<5; i++){ for (int j=0; j<5; j++){ stopsArray[i][j]= new ArrayList<String>(); } } }
Then I use this code to set the stops
public void setNoStops(int stopsNo){ noOfStops = stopsNo; }
[code]...
The bottom written line of code is mentioned in the null pointer error I recieve. Then.Then in my main programme I declare the new object and use these methods the method options displays the list of five stations with a number reference
System.out.println("Please choose a start station :"); options(); place1 = scanner.nextInt(); System.out.println();
System.out.println("Please choose an end station :"); options(); place2 = scanner.nextInt(); System.out.println();
[code]...
mystops is the object I created to store the information.
when compiling I recieve no errors.when I run the program it runs smoothly, asks for the number of stops, allows the user to enter a number, then says enter stop 1, I enter a word and the program crashes giving the error java.lang.NullPointerException
How can I extract data from two different files but produce one output. For example, the first three columns are from text_file_1 and the last column (the last foruth column of the output) is from text_file_2...
I am trying to sum up the elements of an array. When I test my code the sum is always off by one. For example if I input: 20, 40,30 it gives me 89 instead of 90.
This is what I have so far:
public static void main(String[args]){ int size = kbd.nextInt(); int [] myArray = new int [size] //user inputs the elements of array for(int i =0; i<myArray.length; i++){ myArray[i]= kbd.nextInt(); } int total = sumNum(myArray,0, myArray.length-1) System.out.println("The sum is"+ total); }
I'm a complete beginner in Java programming and I'm interested to learn more about its concepts.
Recently, I've been given an exercise which instructs me to display two versions of a picture. The picture to be displayed is provided in the form of a data file of 40,000 digits that are arranged in rows (although there is no marker between rows) and it starts from the top of the picture. So the first digit represents the top left corner of the picture and the last is the bottom right.
Basically, what the exercise wants me to construct a program that plots a dot in one of two colours for each digit. If the digit is in the range 0 to 3 the output should be one colour and for digits in the range 4 to 9 the dot should be in the other colour.
I understand I have to use arrays and also loops to perform this. I'm familiar with the fillEllipse, drawEllipse, drawRectangle and fillRectangle but this exercise is nothing I've attempted before.
When out is equal to the String "2x2.5", the array operations ends up looking like this when it is printed using the toString method:
[, , , x]
As you can see, before the array element x, there are three String variables which only contain whitespace. Why does this occur, and how can I prevent this from happening?
I was a bit confused of the code generated by the Axis2 Code Gen.
I have created a logIn(String username, String password) method in my service and used Axis2 Code Gen to generate the Stub.
I try to access the logIn method from my Client using the Stub like below:
TestServiceStub stub = new TestServiceStub("http://localhost:8080/axis2/services/TestService"); String test = stub.logIn("user","pass").
but instead of UserName and password as the parameters, the Stub created a Login object as the parameter for the logIn method. like the one below:
stub.logIn(Login login1);
I wanted to try the logIn method by providing a static userName and password but it seems impossible because the Stub changed the parameter for the logIn method.
The code here I have works fine if I just want to ask the user to enter four digits: //java application that asks user to input binary numbers(1 or 0) and convert them to decimal numbers import java.util.Scanner; //program uses class scanner public class binarynumber{
//main method that executes the java application public static void main(String args[]){ //declares variables
int digit; int base=2; int degree; double decimal; int binary_zero=0; int binary_one=1; //create scanner for object input
[code]....
The thing is, I want the java application to input more than four digits for the user and I want it to loop it manytimes f until the user ask it to stop.
I need to create a Java program that takes an input a color code in HSV and outputs the equivalent RGB code and Vice versa.
Example: If you test on the color RED in RGB: Input: (255,0,0) Output: (0,100%,100%) If you test on the color RED in HSV: Input0,100%,100%) Output: (255,0,0)
According to what I read, "when programming in Swing, your GUI creation code should be placed on the Event Dispatch Thread (EDT). This will prevent potential race conditions that could lead to deadlock." (See below for code.)
Why is this? How could making a GUI lead to deadlock?
public static void main(String[] args) { SwingUtilities.invokeLater(new Runnable() { public void run() { createAndShowGUI(); } }); }
I have a assignment in which the code has to scrape a web page for a little bit of data including the link to the next page, follow the link, and do this 100 times. It is scraping all the data correctly, including the link, but it isn't following the link to scrape the data on that next page. Instead, it is displaying the first page's data 100 times. I have the code in a while loop where it reads in one character at a time from the page into a string and then uses pattern matching to get the data and the next link from the string. Then it correctly displays the data and should loop back to connect to that next link and read one character at a time into the string and so on.
I have printed the link to the console and it is good. I don't get any errors. I just can't figure out where exactly the problem is. Here is my code:
I have had to create a text analyser. I have created the program but it is all within the main method. The specification states that I have to have at least two methods within my Program.
import java.io.*; import java.text.SimpleDateFormat; import java.util.*; import javax.swing.*; import javax.swing.filechooser.FileNameExtensionFilter; public class Analyser { public static void main(String[] args) throws FileNotFoundException, UnsupportedEncodingException {
According to what I read, “when programming in Swing, your GUI creation code should be placed on the Event Dispatch Thread (EDT). This will prevent potential race conditions that could lead to deadlock.” (See below for code.)
Why is this? How could making a GUI lead to deadlock?
public static void main(String[] args) { SwingUtilities.invokeLater(new Runnable() { public void run() { createAndShowGUI(); } }); }
How do I get my GUI code into a GUI format? I wrote this put it will not make a GUI image.
/* * To change this license header, choose License Headers in Project Properties. * To change this template file, choose Tools | Templates * and open the template in the editor. */ package Ofelia_Inventory_4; import java.awt.*; import java.awt.event.*;
I want to execute my jsp code to compare two dates after every 10 seconds if user enter date and current sys date are equal it will send the mail to the user automatically. Below is my jsp code
this if condition i want to check the date after every 10 seconds and when two dates are equal it will send the mail using below mail code
if(ExpcReDt.compareTo(dateStr)>0) { out.println("Expected return date is greater than current date"); } else if(ExpcReDt.compareTo(dateStr)==0)
public class VargjetUshtrimi2 { public static void main (String a []) { int r[] = new int[11]; for (int i = 1 ;i < 10; i++) {System.out.println( r[i] );} }
The Java-program Matrix below first asks the user for the number of rows and columns in a matrix. After this the program asks for the values of the elements. Finally, program prints the elements of the matrix and their sum on screen. Your task is to create the missing methods. Check the example print to see how to modify the print. When printing the matrix, values on the same row are separated using tabulator.
Program to complete:
import java.util.Scanner; public class Matrix { public static void main(String[] args) { int rows, columns; Scanner reader = new Scanner(System.in); System.out.print("Type in the number of rows: ");
[code]...
Write the missing methods here / Methods are written in the text box below.
Example output
Type in the number of rows: 3 Type in the number of columns: 4 Type in the element 1 of the row 1: 1 Type in the element 2 of the row 1: 2 Type in the element 3 of the row 1: 3 Type in the element 4 of the row 1: 4 Type in the element 1 of the row 2: 5
[code]...
Matrix:
1 2 3 4 5 6 7 8 9 10 11 12
Sum of the elements of the matrix: 78
my code
import java.util.Scanner; public class apples { public static void main(String[] args) { int rows, columns; Scanner reader = new Scanner(System.in); System.out.print("Type in the number of rows: ");
So I am finishing up a GUI that randomly rolls a dice and shows you the dice face from a file that I have on my computer. It compiles fine, but when I open the GUI and press the button "Roll" it gives me errors and does not display the images.
I am pretty new to Java and I am working on a sample Search code from my textbook. I can't figure out why I am getting the following error because I copied the sample exactly as it is in the book. The error is illegal start of expression on the second to last line.
public class Search { public static final int NOT_FOUND = -1; public static int binarySearch( int [] a, int x ) { int low = 0; int high = a.length - 1; int mid;
