How To Get Double Variable From Keyboard Input

Apr 8, 2014

I am testing to get a double value from keyboard input as below?

import java.util.Scanner;
public class EchoLine{
public static void main(String[] args){
double amount;
Scanner myScanner=new Scanner(System.in);
amount=myScanner.nextDouble();
System.out.println(amount);
}
}

I type 5.95 in Console View of Eclipse but as a result I get an error on line 9.

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I am trying to make a program that calculates the change due in dollars and cents. The user inputs both the amount due and the amount tendered. My program only works with whole numbers?

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I am trying to create this program I am pretty sure it is easy but I am making it difficult lol, it keeps giving me a error, it is saying cannot find symbol - variable keyboard, I don't think I have keyboard as a variable but I may be wrong.

double distancel = keyboard.nextdouble(); that is the specific line ....

import javax.swing.JOptionPane;
import java.io.File;
import java.util.Scanner;
//import java.util.totalInches;
//instance variables
public class Map{
public static void main(String[] args){

[Code] ....

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a code that will add 1 to a variable and store it anytime key "p" is pressed on the keyboardKeep in mind

Here's what i have....

import java.util.Scanner;
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public static void main(String args[]){
Scanner kin = new Scanner (System.in);
int pa, ma;

[Code]...

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[code]....

What i want to do is that if the number is greater than 50 to count until 100. else if the number is less than fifty to count for example from 36 to zero.

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Here is my code:

import java.io.*;
public class q7
{
public static void main(String[] args)
{
InputStreamReader ISR=new InputStreamReader(System.in);
BufferedReader BR=new BufferedReader(ISR);
 
[code]...

.But when I use Command console to run this it says: 1111.jpg. I also wanna know is there another way to do this with switch- case statements.

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Sep 23, 2014

I need to design, implement, and test a program to input and analyze a name. The program begins by retrieving a user input string from the keyboard. This string is intended to be the user's name. These are the errors we have to search analyze the user input for: No blanks between names firstName and lastName, Non-alphabetic characters in names, Less than two characters in first name, and Less than two characters in last name. Each of these errors must be thrown. All exceptions must be derived from a programmer-defined class called NameException. Each exception should use a detailed message to differentiate among the file types of errors.

This is the format of my NameException class, is the format itself correct? I will fill in the details of each exception I am just wondering if that is how I should set it up.

public class NameException extends Exception {
private String firstName, lastName;
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}
public NonAlphabeticalCharactersException(String firstName, String lastName) {

[Code] .....

I was told not to try and catch thrown errors in the main method, would I just create another method in the Driver class to take care of that then?

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I can not enter Latin letters with macron (Latvian specific characters) in JavaFX programs. Instead something like Latin letters with acute are entered.
 
what I need to enter is characters like this: Latin letter "a" with macron

Browser Test Page for Unicode Character 'LATIN SMALL LETTER A WITH MACRON' (U+0101)
 
what is actually entered: Latin letter "a" with acute

Browser Test Page for Unicode Character 'LATIN SMALL LETTER A WITH ACUTE' (U+00E1)
 
There are several keyboard layouts available for Latvian language input. Problem persists only on Windows OS for layouts using tilde key or apostrophe key as deadkeys. There are no problems with Microsoft Latvian (QWERTY) layout that uses ALTGR key as deadkey. There are also no problems on Linux OS using keyboard layouts that causes problems in Windows OS. I also noticed that character input works as expected int SceneBuilder 2.0 (I believe it has been build with javaFX). There are no problems also in java Swing GUI framework. So could this be a bug in JavaFX or am I missing some configuration settings?
 
How can I enter latin letters with macron using keyboard layout that uses tilde deadkey?

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Jun 21, 2014

I typed the following program using BlueJ

import static java.lang.System.out;
import java.util.Scanner;
import javax.swing.JFrame;
public class Main {
public static void main (String args[]) {
Scanner read = new Scanner (System.in);
out.print ("> ");
double num = read.nextDouble();
out.println (num);
}
}

When I compile the code it gives me no errors; however when I run the program and write a floating point number it gives me the following message:

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I used to use an online compiler and the nextDouble() method worked perfectly there.

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Attempted User Input Using A Double

Jan 13, 2015

For some reason, the below code is not working out for me. I thought I had the scanner right and Eclipse is only throwing an error on the last line that states "else(ernie == 0)". What am I missing here?

Basically just trying to take user input, incorporate some if and else if statements to return a line based on if the condition is met.

Java Code:

import java.util.Scanner;
//Importing the scanner now for user input
public class Ernie {
public static void main(String[] args) {
double ernie;

[Code] .....

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May 2, 2014

I am supposed to write a program on PuTTY using UNIX (I have Windows 8), but I am not comfortable with it yet, so I am using Java through NetBeans (IDE 7.4).

The program has to follow these instructions (ignore the Linux part of the instructions, the rest is in bold):

Write a program on the Linux system using the putty utility. The program should get strings of data from the command line (that is, look for the data in the "args" array of strings). Use a loop to convert each of the strings in the array into a double and add the number to a total. Print the total after all of the strings have been processed.

The program will use try-catch to catch any error that occurs. If an error occurs, the program will print a message saying that the error occurred. The program can end at that point.

You should create the Java program using the nano editor. The input data should be a list of numbers on the line that runs the program.

The problem so far is that I keep getting an error when converting a String value into a new double value. I have yet to code the try-catch method in my program

Java Code:

import java.util.*;
public class Program13Strings {
public static void main(String[] args) {
Scanner scan = new Scanner (System.in);
System.out.println("How many lines of data do you wish to enter?");
int size = scan.nextInt();

[Code] ....

*NOTE: right where my code says double newDouble = Double.valueOf(newResponse); is where the error is occurring.

*ERROR: Exception in thread "main" java.lang.NumberFormatException: For input string: "abc"

at sun.misc.FloatingDecimal.readJavaFormatString(Floa tingDecimal.java:1241)
at java.lang.Double.valueOf(Double.java:504)
at program13strings.Program13Strings.main(Program13St rings.java:21)

Java Result: 1

How can this be fixed so I don't get this error?

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I am writing a code in which a user inputs data as a string and that data must be verified as a valid number. A valid number is anything from 0-100. Then all valid numbers are converted into double numbers.

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Is it suppose to be an if, else statement? And if so how is it suppose to be validated?

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import java.awt.event.*;
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import java.awt.*;
public class TextGUI extends JFrame{
     public TextGUI(){
          super("Text Test");
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[Code] ....

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Here, below is my code..

<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
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<html>
<head>
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Okay, so I know how to get user input and create a variable from the input, create a basic addition sum etc...

So I have this code:

package calc;
import java.util.Scanner;
class calc{
private static final double add = 0;
private static final double subtract = 0;
public static void main(String args[]){

[Code] .....

I'm basically trying to make it so that when the user enters tnum, tnum2, tnum3 and tnum4, their answer turns to the variable which has to be either true or false to make the boolean work. I don't know really how to do this. I want to make it so that if they enter yes, then that makes the boolean true and the numbers will multiply and create the answer variable. If they enter no then the boolean is false and it moves onto the next if statement. How can I do this?

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Java Code:

String options = JOptionPane.showInputDialog(null, "In your decision, how many options do you have?
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Variable Fields are not holding information through constructor from user input so here's what I did instead.

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so i'm following a java tutorial from the book and it has a few challenge questions. and i'm stucked on one. i think i just don't understand what is it that its asking me. heres the question, Write a statement that reads a user's input integer into the defined variable, and a second statement that prints the integer. assuming scanner is given, and i checked my heading code is ok.
 
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and

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private MyObj obj;
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Is there a difference in performance or usability? (Given also the case there are no static calls expected) ....

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I read in a discussion forum that when local variables are declared (example code below), their name reservation takes place in memory but they are not automatically initialized to anything. On the other hand, when member variables are declared, they are automatically initialized to null by default.

Java Code: public void myFunction () {
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I am writing a code that tries to figure out the users password by going through every possible key (brute force). Although I think its going to work, it looks EXTREMELY inefficient to me, since its just a huge switch statement for each character -- 94 total, including the shift values. Is there a built in method in the JAVA API that goes through every key or something?

Here is my code for that segment:

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why we are not able to read second string in this program.

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Note: If I uncomment line num 9 it works fine

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Feb 20, 2014

Write a program that extracts words from a file. For the purposes of this program, a word is defined as a series of adjacent letters. Only print words that are at least four and no more than 12 letters long. Print each word on a different line.

The program should read the name of the file from the keyboard.

************************************************** ************************************************** **************

I need to get the filename from the user for this particular program. Usually I would have the name of the file prewritten into the source code like this....

Scanner input = new Scanner(new File("gettsy_burg.txt");

I tried different ways but I just can't seem to figure it out.... I guess what I'm really asking is how to rearrange Scanner input = new Scanner(new File("gettsy_burg.txt"); since I want the user to input the filename instead of the filename being prewritten by the programmer(me).

This is what I have so far to let the user for input....

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