The area of a square is stored in a double variable named area . Write an expression whose value is length of the diagonal of the square. Do I use math.sqrt?
View RepliesI have a math expression in a String, that I want to split into 4 pieces as in the following example:
String math = "23+4=27"
int num1 = (23 STORES HERE)
int num2 = (4 STORES HERE)
String operator = (+ STORES HERE)
int answer = (27 STORES HERE)
Note that the operator can be either + - * /
I'm trying to write a sales tax program with JOptionpane but I received this message: illegal start of expression
import javax.swing.JOptionPane;
public class SalesTax {
public static void main(String[] args) {
String amount;
double stateSalesTax;
double countySalesTax;
double totalSalesTax;
double totalSaleAmount;
double amt;
JOptionPane.showInput.Dialog("Enter the amount of purchase");
[code]....
I'm trying to create a cursor for a game that moves square by square. While it will move to the next square, though, it leaves the image of the previous cursor on the last square it was on.
As a visual explanation, this is what the program looks like on launch:
This is what it's suppose to look like after you press the right arrow key once (made by forcibly changing launch coordinates):
And this is what it actually looks like after you press the right arrow key once:
Here is the code for the program:
package cursortest;
import javax.swing.*;
import java.awt.*;
import javax.imageio.*;
import java.io.*;
import java.awt.event.*;
public class CursorTest extends JPanel implements KeyListener{
[Code] ......
I'm fully aware that I could just use g.clearRect on the area and remove it for sure, but I know for a fact I shouldn't have to as I have another program I made a long time ago that tried to do something similar without needing to resort to that.
How would I compare the square of the square root of any number. The difference in these values is due to the rounding error in Java.
Example: Enter number 2
The answer I should get is: 2.000000000000004
Round off error: -4.440892
I'm trying to convert a Formula to run in a java program.
This is the formula:
(you can ignore the modifier part)
This is my attempt. However it prints out 0.0
import java.util.Scanner;
public class DamageCalc{
public static void main(String[] args){
Scanner s = new Scanner(System.in);
[Code].....
i am trying to calculate the number of months it takes to pay off a set amount of credit card debt given the following information: principle amount, annual interest rate, and monthly payment. How to import the formula necessary to system.out.print the answer (number of months it takes to pay off debt) ???
View Replies View RelatedI am doing this math for my assignment where you have to find the imaginary number.
double dem = (b*b-4*a*c)*-1;
double dem2 = Math.sqrt(dem);
realPart = (-b/(2*a));
imagine = (dem2)/(2*a);
imagineneg = (dem2)/(2*a);
So basically I am trying to get it that the number inside the square root isnt negative. So lets say I enter a: 1, b: -1, c: 4.25. When you do the discriminant it would be -16 but I want that to be positive so I multiple it by -1 (thats the dem part). Then I sqaure root the whatever the answer is and then go to the imagine and imagineneg part where you find the imaginary number.
My problem is that instead of it being -16*-1 to get 16, some how I get 15.
I need to create a diagonal cross however I can not figure out how to do the upper left side of it.
Currently I am getting
0*
1--*
2---*
3 *--*
4*-----*
I want to get it to look like
0*------*
1 *--*
2----*
3 *---*
4*------ *
( I replaced spaces with -) So far I have
System.out.println("Input a size(must be larger than 1: )");
size=input.nextInt();
if (size>1) {
for (x=0;x<size;x++){
System.out.println("");
[Code] ....
I am just trying to move a rectangle in a diagonal line. When the applet pops up, the rectangle is there but doesn't move. If I drag the sides of the applet to make it bigger or smaller the rectangle will redraw itself and move, but I want it to move without touching the window.
Java Code:
package javaapplication3;
import java.applet.Applet;
import java.awt.*;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.Random;
[Code] .....
Why does it only repaint when I resize the window?
I defined a java class thus:
class Info{
public String name;
public String version;
public String arch;
double CPUSpeed;
double ranUtil, CPUUtil;
};
But each object of such a class takes many bytes. How can I limit it to one fourth of a Kilo-Byte?
how you can do array.length, I have an array with [][][][], and what do I do to find the length of one section?
So let's say
Java Code: int array[][] = {
{5, 5, 5, 5},
{4, 4, 4, 4},
{3, 3, 3, 3}
} mh_sh_highlight_all('java');
How do I find out the length of the {5, 5, 5, 5} which is 4. Because there are 4 place-holders.Is there a way?
I need to make a program that does stripes, checkerboard, and double diagonal. I can not get the stripes to work?
import java.util.Scanner;
public class AsciiArt {
public static void main(String[] args){
int pattern;
Scanner input=new Scanner(System.in);
System.out.println("Choose one of the following patterns by pressing the corresponding number");
System.out.println("1) Stripes");
[Code] ....
Write a program that prompts the user to enter an integer m and find the smallest integer n such that m * n is a perfect square. (Hint: Store all smallest factors of m into an array list. n is the product of the factors that appear an odd number of times in the array list. For example, consider m = 90, store the factors 2, 3, 3, 5 in an array list. 2 and 5 appear an odd number of time in the array list. So, n is 10.)
so far my program is just like this.
import java.lang.Math;
import java.util.Scanner;
public class PerfectSquare {
public static void main(String[] args) {
Scanner m = new Scanner(System.in);
int Fint;
[Code] .....
how do i make the program find the smallest integer n?
Coding (must follow pseudocode algorithm provided) for comparing characters of a word to a puzzle board char[][].
I've gotten the horizontal and vertical searches to work, but I'm having a difficult time figuring out how to search diagonally.
Here's the search algorithm format I have to use:
for each guess word
for each letter of the puzzle
for each letter of the guess word
check for diagonal match
if found, add word to list, break to next guess
I'm assuming there should be a +1 horizontal offset after I find the first letter, but every index I've bumped has caused me to screw up my array bounds. I'm missing something.
Here's the algorithm I'm using for diagonal search. This same algorithm worked for vertical search (minus the offset of course)
//diagonal search
for(String word : guessWords) {//for each guess word
int letterCount = 0;
int index = 0;
for(int j=0; j<grid[index].length; j++) {//for each puzzle letter
[Code] ....
I have written below regex for two lines.
String LN1Pattern = "^((?=.{1,35}$)(/([A-Z]{1,5})(|(//[a-zA-Z0-9]+))))$";
System.out.println("/ABC//FGhiJkl012345".matches(LN1Pattern));
String LN2Pattern = "^(|((s+(//[a-zA-Z0-9]{1,33})){1,2}))$";
System.out.println("".matches(LN2Pattern));
s+ is a newline character.
But when I combines both as below, its not giving me expected result.
^(((?=.{1,35}$)(/([A-Z]{1,5})(|(//[a-zA-Z0-9]+))))(|((s+(//[a-zA-Z0-9]{1,33})){1,2})))$
For string "/ABC//FGhiJkl012345
//abCD01EF02" - returns False. Expected is True
I think there is some problem in lookahead placed.
In this i Write a Java program to parse a syntactically correct arithmetical expression and produce an equivalent Expression TREE. Remember, in an expression tree the terminal nodes are variables and constants, and the interior nodes are operators (such as +,-,*,/). For instance the expression: (1 + 2) * 3 can be represented by the following tree:
INPUT Expression
(1 +2)*3
POSTORDER Expression
1 2 + 3 *
TREE [root=asd.reg.Node@56ddc58]
But when I Execute the program it Shows only Prefix and postfix .But the requered output is in inorder preorder and postorder ...
import ava.io.BufferedReader;
import java.io.FileReader;
import java.io.IOException;
import java.util.Scanner;
import javax.swing.tree.TreeNode;
[code]....
I need a regular expression in java for phone number which that does not allow any character special character only numbers should be allowed.. My sample program is
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class c {
public String removeOrReplacePhoneNumber(String input) {
if (null == input)
return input;
[Code] ....
but this is allowing characters like a,b,c..
I need to parse an html web page to extract specific information from the tags in Java. For example,
<b>Species </b> Strain </td>
I need to look for the Strain info (Strain is variable in length) in the page. The whole web page is stored as a huge string. I need a regular expression that can identify all the Species and retrieve their corresponding strain info. how to do this or can propose some clever string manipulation methods in Java.
I am trying to implement an example (Book* : Java SE 7 ..By S G Ganesh) for validating an IP address but it fails to validate a valid IP addresses. I found another example on the internet(**) and it works super fine, no problem at all. I edited the code (the one I got from internet) into the exact format like book and it still works super but i don't understand why the books' example doesn't work though both look exactly the same now ,further more, how can i compare String x and y for equality?
public class TestClass {
void validateIP(String ipStr) {
String one = "((25[0-5]|2[0-4]d|[01]?dd?)(.)){3}(25[0-5]|2[0-4]d|[01]?dd?)"; //copied from internet and edited
String two = "((25[0–5]|2[0–4]d|[01]?dd?)(.)){3}(25[0–5]|2[0–4]d|[01]?dd?)"; // copied from book
String x = "((25[0-5]|2[0-4]d|[01]?dd?)(.))";
String y ="((25[0–5]|2[0–4]d|[01]?dd?)(.))";
[Code] ....
I have the following structure and want to use lambda expressions with it, but an exception occurs:
class SuperClass // (package private)
public class SubClass extends SuperClass // in same package as SuperClass
I have a functional interface (a listener), which has one argument of type SubClass.
public interface MyListener() {
void myMethod(SubClass e);
}
When I use the old-school Java 7 style:
addListener(new MyListener() {
@Override
public void myMethod(SubClass e) {
System.out.println(e);
}
});
Everything works fine! If I use Java 8 lambda expression instead:
addListener(e -> {
System.out.println(e);
});
It will throw an exception:
java.lang.IllegalAccessError: tried to access class SuperClass
Do not want to use loop and Character.isLetter to validation string , not sure at how to using regular expression?
If I want 8 characters string length, the first 3 is letter, the remind character is number ...
^[a-z0-9_-]{8}$
^[a-zA-Z]{3} + [/d]{5} $ ??
I have a text file that has the following lines:
the boy is smart
He is from Australia
** Highly important line
That's all
Now, I need a regular java expression that would match a line in this file that begins with the ** characters. That is, when I match the text with the regex, I should get only this line :
** Highly important line
How would I write this regex in java?
I Write a Java program to parse a syntactically correct arithmetical expression and produce an equivalent Expression TREE. Remember, in an expression tree the terminal nodes are variables and constants, and the interior nodes are operators (such as +,-,*,/).
For instance the expression: (1 + 2) * 3 can be represented by the following tree:
INPUT Expression
(1 +2)*3
POSTORDER Expression
1 2 + 3 *
TREE [root=asd.reg.Node@56ddc58]
But when i Execute the program it Shows only Prefix and postfix .But the requered output is in inorder preorder and postorder so how to solve these error
import java.io.BufferedReader;
import java.io.FileReader;
import java.io.IOException;
import java.util.Scanner;
import javax.swing.tree.TreeNode;
public class InToPost {
private static String str;
[Code] .....
I'm trying to calculate sin(x) without using Math.sin(x). The formula for sin(x) is: x - x^3/3! + x^5/5! ... I can't seem to get the coding for the alternating +/- right. Here's my program:
import java.util.Scanner;
import java.lang.Math;
class Sin
{
public static void main(String[] args)
{
Scanner kb = new Scanner(System.in);
int n, c, fact = 1, count = 1;
double x, sum = 0, sum_sin = 0, result;
[Code] ....
Here is the assignment:
Prompt the user to input two sides (a and b) of a right triangle. Calculate, using the
formulas below, the hypotenuse and the other two angles of the triangle. Calculate the
perimeter and the area.
Here are the formulas:
a^2 + b^2 = h^2
sinθ = a/h
A + B + C = 180 degrees
how to start this program out, i know which math classes i need to use.