Asking User To Put In Radius Of A Circle To Calculate Area / Diameter And Circumference
Mar 5, 2014
I am doing an assignment that is asking for the user to put in the radius of a circle and the program figures out the area, diameter and circumference. It is using 2 different java programs to accomplish this. One with the info on how to get area, diameter and circumference and one is the demo that runs the program. I keep getting errors on my demo.
// Circle Class
public class Circle {
private double rad;
private double Pie;
private double area;
private double diameter;
//program that calculates the circumference and area of a circle
import java.util.Scanner; public class circle{ public static void main(String[] args){ Scanner input= new Scanner( System.in); double r; //declares radius
[Code] .....
And here is what is displayed in the command prompt when I compile my code:
circle.java:17: error: cannot find symbol r.input.nextdouble();//entered the radius symbol: method nextdouble() location: variable input of type Scanner 1 error
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;
package areatest; import javax.swing.JOptionPane; public class AreaTest {
public static double areaTriangle (double length, double width){ //How to calculate the area of a triangle return .5f * length * width;
[Code] .....
When I try to get the area of a rectangle it gives me 9 no matter what input I give it. When I try to get the area of a triangle it gives me .5 no matter what input I give it. Same with the circle but it always gives me 12.56370...
How do you use power of math. I'm trying to write a calculator to calculate the volume of a cylinder by asking the user to enter the height and radius but when I use pow(2) it doesn't work. I imported java.lang.math class so i dont have to keep using math. for now my code runs just fine since I'm using radius * radius but I would really luv to use the power instead times each other when i have to use higher powers.
import java.util.Scanner; import static java.lang.Math.*; public class Lab2 { public static void main(String[] args) { Scanner scan = new Scanner(System.in);
What's that diameter? Create a new method for the circle class called diameter. Add this method to the circle class described on page 15-1. It should return a double that is the diameter of the circle. No parameters are passed to this method.
In a tester class, test the performance of your new diameter method as follows:
(Your project should have two classes, Tester and Circle.)
here is what i have so far:
public class Circle { public Circle (double r) { radius = r; } public double area() { double a = Math.PI * radius * radius;
I have two classes LightController & Circle. I need to use the LightController class to do the following:
Creates an instance of Circle with a diameter of 50 and a colour of OUColour.GREEN and assigns this new circle to the instance variable light.
Sets the xPos of light to 122. Sets the yPos of light to 162.
I am struggling to write the correct line of code to set the colour to green and set diameter to 50.
Code for the two classes below.
import ou.*; import java.util.*; /** * Class LightController * This class uses the Circle class, and the Shapes window to simulate a disco light, that grows and shrinks and changes colour. */
public class LightController { /* instance variables */ private Circle light; // simulates a circular disco light in the Shapes window private Random randomNumberGenerator;
Here is the program I wrote for calculating the circumference of a circle.
//circumference.java //program that calculates the area and circumference of a circle import java.util.Scanner; //program uses class scanner public class circumference{ //main method begins execution of Java application public static void main(String args[]){
[Code] .....
Even though my code compiles and runs without any errors, the program doesn't calculate the circumference.
I have to print points on a circle in increments of -0.1, but when I use a number larger than 1.3, the list stops at 0.1 larger than negRadius, and I don't know why. (Assume the center is (0,0))
public class PointsOnACircleV1 { public static void main(String[] args) { double radius = 1;
(Corner point coordinates) Suppose a pentagon is centered at (0, 0) with one point at the 0 o’clock position. Write a program that prompts the user to enter the radius of the bounding circle of a pentagon and displays the coordinates of the five corner points on the pentagon. Here is a sample run:
Enter the radius of the bounding circle: 100 The coordinates of five points on the pentagon are (95.1057, 30.9017) (0.000132679, 100) (-95.1056, 30.9019) (-58.7788, -80.9015) (58.7782, -80.902)
What we know , we know both the radius of the circle(user inputted) and the side of the pentagon from formula (double side = 2 * radius * Math.sin(Math.PI/5)) .We also know that one point is (0 .100) Also i know that the distance between 2 points is Math.sqrt(Math.pow(x1 - x2 ,2) - Math.pow(y1 -y2 ,2)) .
There might be other ways to solve it but this is my best bet trough i dont remember how to solve linear equations of the form x^2 + y^2 = - radius and radius ^2 = x^2 + (y - 100) ^ 2..
The solution i found is using the radius from the center to the point we want to find out and using the radius to the point we already know ( 0 .100) but i have to solve that damn equation first ...
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
public class PondRadius { public static void main (string[] args) { //Calculate the radius of a pond //which can hold 20 fish averaging 10 inches long int fishCount = 20;//number of fish in pond int fishLength = 10;// Average fish length int inchesPerFoot = 12;//number of inches in one foot
[Code] ....
And here is the error or exceptions i received
C:javaLesson1>javac PondRadius.java PondRadius.java:23: error: ')' expected System.out.println("To hold" + fishCount + fish averaging " + fishLength +" inch es long you need a pond with an area of " +
I am able to draw this image using filloaval() but afterwards when i am calculating some area i have to shade that in the figure in some different color
Basically its a program where a user is prompted to enter the length of all three sides of a triangle and the program calculates the area by herons formula and can tell if the triangle is equilateral or Pythagorean. I am having trouble entering a formula to where all three enter sides cant possibly be a triangle. Here is my Program. Where the '?' is stated.
import java.util.Scanner; public class Triangle { public static void main(String[] args){ double a; double b; double c; double s; double x; double area;
Create a program to input the length and width of a rectangle and calculate and print the perimeter and area of the rectangle. To do this you will need to write a Rectangle class and a separate runner class. Your program should include instance variables, constructors, an area method, a perimeter method, a toString method, accessor and mutator methods, and user input. Your runner class should include 3 Rectangle objects. One default rectangle, one coded rectangle, and one user input rectangle. All methods should be tested in the runner class.
This is my code:
import java.util.Scanner; public class Rectangle { double length; double width; public Rectangle() {
[Code] ...
What have I done??? I have created this program using the few different resources with which I am supplied, but I don't understand the resources.
Write a Java program that calculates the area and volume of a cube, sphere, cylinder, and regular tetrahedron. Your program should obtain the necessary input for each of the objects from the console and output the input, area, and volume of the object. Use appropriate messages to guide the user of your program.
I'm supposed to take an input from the user and calculate the value of pi using this formula: 1/1 - 1/3 + 1/5 - 1/7 etc... so on alternating between minus and plus and denominator increasing by 2 every time. If the user inputs the number 3, then it should print (1/1 - 1/3 + 1/5 - 1/7 + 1/9) *4. The idea here is that the higher the input of the user is, the higher the equation will be close to pi.
This is what i have so far :
import java.util.Scanner; public class Pi { public static void main(String[] args) { double first = 1/1; double second = 1/3; Scanner input = new Scanner(System.in); System.out.println("Enter a Number to calculate how far you want the formula to perform: "); double count = input.nextDouble(); } }
This is literally all i have, i know i need a while loop and an if loop.
I'm supposed to write a GUI application letting the user enter a file on the text field and display its hex representation in a text area and vice versa.
Here's my code:
/* * 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 hexconvertor; import java.util.*; import java.io.*; public class HexConvertor extends javax.swing.JFrame {
I have to create a program that calculates the nth Fibonacci number and returns that to the user. Fibonacci said his number sequence would describe the ideal breeding patterns of immortal rabbits. So, you are going to make this vision a reality.
First, take in a numeric value from the user and calculate that value in the fibonacci series. Next, find an image of a rabbit and display the image on a GUI (put the image as an icon on a label!) the number of times returned by the algorithm (Put all the aforementioned labels on one panel with FlowLayout!).
You need to remove the old images from the Panel. Probably the easiest way to do this is to create a whole new panel and remove the old one (hint: the remove method of JPanel should come in handy)
You could use an array of JLabels You will need to create a new JLabel and add each member of the array to the panel I should be able to scroll to see any images that are off screen
I am having difficultly on to making the array list for JLabel, and getting the Fibonacci sequence to show the pictures of rabbits. Below is my current code.
import java.awt.FlowLayout; import java.awt.*; import java.awt.event.*; import javax.swing.*; public class Rabbit extends JFrame
This is the first time we are using 2 different classes. This is the code I have so far. What I am having trouble is doing the calculations and storing the value into the planet the user selected and keeping it going. I will attach the instructions ....
public class FakeGravity{ // Instance variables private String planet; private int VelocityDecay; private double BouncinessFactor; // default constructor public FakeGravity(){
I am trying to create a user defined Exception. I am using a hard-coded value in the constructor of circle class at the time of object creation.But in the constructor this value becomes 0.
import java.lang.Exception; import javax.swing.*; class InvalidRadiusException extends Exception{ private double r; public InvalidRadiusException(double radius){ r = radius;
[Code] ....
Due to this its always generating InvalidRadiusException even if i am supplying a non-zero non-negative value.
Write a program that draws 20 circles, with the radius and location of each circle determined at random...... Two circles overlap if the distance between their center points is less than the sum of their radii...
There may be many problems with the code in general but what I'm struggling with is the distance and the totalradius portion. Visually, its inaccurate.
import java.awt.*; import javax.swing.*; public class CircleTest extends JPanel { Circle []circles; Circle []circleCenter; Circle []all; private int distance, totalradius, dx, dy; private int radius,x,y;
