Is there a way to graph the values outputted by the following code in a separate class.
import java.util.Scanner;
public class scannerNumber {
public static void main(String []args) {
Scanner originalNumber = new Scanner(System.in); // number for input
System.out.println("Enter a number: "); // asks for input
int firstNumber = originalNumber.nextInt();
double secondNumber = Math.abs((firstNumber*Math.sin(firstNumber)));
System.out.println("Your new number is: " + secondNumber);
originalNumber.close();
}
}
Scanner originalNumber = new Scanner(System.in); // number for input
ArrayList<Double> results = new ArrayList<Double>;// array for results
System.out.println("Enter a number: "); // asks for input
int firstNumber = originalNumber.nextInt();
for(int i=0; i<=firstNumber; i++){
double secondNumber = Math.abs((firstNumber*Math.sin(firstNumber)));
results.add(secondNumber);//add results to an array
}
for(int k:results)
System.out.print(k+" ");
originalNumber.close();
this will create an array that contains y values while x is between [0,firstNumber]
note that this not a complete answer for your question. you should start with basics.
complete tutorial for function drawing in java
. you can use this tutorial but first look at gui for java.
Related
Hello I'm new in java and as i was making a program practicing input/output methods I came to this error:
When I input a int value the program works well, but when I input a double value it shows me this:
Here is my code:
import java.util.Scanner;
public class InpOutp
{
public static void main(String[] args)
{
Scanner in = new Scanner(System.in); // creates a scanner
System.out.print("Enter price of a six-pack beer: ");
double packPrice = in.nextDouble();
System.out.print("Give the ml of a can: ");
double canMl = in.nextDouble();
final double CANS_PER_PACK = 6;
double packMl = canMl * CANS_PER_PACK;
// find the price per ml of a pack
double pricePerMl = packPrice / packMl;
System.out.printf("Price per ml: %8.3f", pricePerMl);
System.out.println();
}
}
The problem is the separator. If you wish to use period try this
Scanner in = new Scanner(System.in).useLocale(Locale.US);
EDIT:
Also it is worth to mention, you should use in.nextLine();
after every nextInt() or nextDouble() otherwise you will encoder problems with nextLine when entering text.
Try this
System.out.print("Enter price of a six-pack beer: ");
double packPrice = in.nextDouble();
System.out.println("this will be skipped" + in.nextLine());
System.out.print("Give the ml of a can: ");
double canMl = in.nextDouble();
in.nextLine();
System.out.print("And now you can type: ");
System.out.println(in.nextLine());
The fault was that I was typing the values with . (5.4) and I should type them with , (5,4).
I'm trying to store the sum of 2 numbers inside a while loop so that once the loop ends multiple sums can be added up and given as a total sum, however I am rather new to Java and am not sure how to go about doing this.
I'm trying to use an array but I'm not sure if it is the correct thing to use. Any help would be greatly appreciated.
import java.util.Scanner;
public class StoredWhile{
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
int TotalNum[]=new int[10];
Int Num1, Num2, AddedNum;
String answer;
do{
System.out.println("Please enter a number");
Num1 = input.nextInt();
System.out.println("Please enter a second number");
Num2 = input.nextInt();
AddedNum = Num1 + Num2;
System.out.println("The sum of the two entered numbers is " + AddedNum);
TotalNum[0]=AddedNum;
TotalNum[1]=;
System.out.println("Would you like to calculate the sum of two more numbers (y/n)?");
answer = input.next();
}
while (answer.equals("y"));
System.out.println("The total sum of all the numbers you entered is " + TotalNum);
}
}
There is a data container called ArrayList<>. It is dynamic and you can add as many sums as you need.
Your example could be implemented like this:
public class StoredWhile{
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
ArrayList<Integer> listOfSums = new ArrayList<>();
int Num1, Num2, AddedNum;
String answer;
do{
System.out.println("Please enter a number");
Num1 = input.nextInt();
System.out.println("Please enter a second number");
Num2 = input.nextInt();
AddedNum = Num1 + Num2;
System.out.println("The sum of the two entered numbers is " + AddedNum);
listOfSums.add(AddedNum);
System.out.println("Would you like to calculate the sum of two more numbers (y/n)?");
answer = input.next();
}
while (answer.equals("y"));
// Then you have to calculate the total sum at the end
int totalSum = 0;
for (int i = 0; i < listOfSums.size(); i++)
{
totalSum = totalSum + listOfSums.get(0);
}
System.out.println("The total sum of all the numbers you entered is " + totalSum);
}
}
From what I see, you come from a background of C# (Since I see capital letter naming on all variables). Try to follow the java standards with naming and all, it will help you integrate into the community and make your code more comprehensible for Java devs.
There are several ways to implement what you want, I tried to explain the easiest.
To learn more about ArrayList check this small tutorial.
Good luck!
Solution with array:
import java.util.Scanner;
public class StoredWhile{
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
int TotalNum[]=new int[10];
int Num1, Num2, AddedNum;
String answer;
int count = 0;
do{
System.out.println("Please enter a number");
Num1 = input.nextInt();
System.out.println("Please enter a second number");
Num2 = input.nextInt();
AddedNum = Num1 + Num2;
System.out.println("The sum of the two entered numbers is " + AddedNum);
TotalNum[count]=AddedNum;
count++;
System.out.println("Would you like to calculate the sum of two more numbers (y/n)?");
answer = input.next();
}
while (answer.equals("y"));
int TotalSum = 0;
for(int i = 0; i <count; i++ ) {
TotalSum += TotalNum[i];
}
System.out.println("The total sum of all the numbers you entered is " + TotalSum);
}
}
This solution is not dynamic. There is risk that length of array defined on beginning will not be enough large.
I need to accept a String input and a double input from a user and store them into two parallel arrays to create a shopping cart.
I have initialized both arrays to a user determined size Amount and created a for loop to run for the inputs and store the values in the two arrays, and have set an extra input.nextLine() so the code will swallow the new line created at the end of the loop. This is my code so far,
import java.util.*;
import java.io.*;
public class Item
{
public static void main(String[] args)
throws java.io.IOException
{
int amount;
String nextItem,I;
Scanner input = new Scanner(System.in);
System.out.println("Please enter the number of items you would like to add:");
amount = input.nextInt();
String cart[] = new String[amount];
double price[] = new double[amount];
for(int i = 0; i<amount; i++)
{
System.out.println("Please enter the name of an item:");
cart[i] = input.nextLine();
System.out.println("Price?");
price[i] = input.nextDouble();
input.nextLine();
}
}
}
However when the program runs the loop it runs both System.out.println commands skipping past the first input.nextLine(), and will only accept an integer input.
use two scanner class
Scanner sc=new Scanner(System.in);
Scanner sc1=new Scanner(System.in);
int p[] = new int[3];
String n[] = new String[3];
for(int i = 0; i < p.length; i++){
System.out.print("Name: ");
n[i] = sc.nextLine();
System.out.print("Percentage: ");
p[i]=sc1.nextInt();
// use two scanner class
I've been having issues catching non numbers.
I tried try / catch but I can't grasp a hold of it. If anything I get it to catch non numbers, but doesn't let the user try entering again... It just stops my code completely.
Here is my code:
package triangle;
import java.util.Scanner;
public class traingle {
public static void main(String[] args){
//explaining what the program is going to do
System.out.println("You will be able to enter 3 angles to equal the sum of a triangle,\nthis automated program will tell you if the angle you entered is issosoliese, eqilateral or scalene");
//creating input 1,2,3 for user
Scanner angle1 = new Scanner(System.in); // Reading from System.in
System.out.println("Enter angle degree number 1: ");
int n = angle1.nextInt();
Scanner angel2 = new Scanner(System.in);
System.out.println("Enter angle degree number 2: ");
int n2 = angel2.nextInt();
Scanner angel3 = new Scanner(System.in);
System.out.println("Enter angle degree number 3: ");
int n3 = angel3.nextInt();
//this is just telling how much degrees the user had in total if they didnt match up to triangle standards
This should get you started.
package triangle;
import java.util.Scanner;
public class triangle {
public static void main(String[] args){
//explaining what the program is going to do
System.out.println("You will be able to enter 3 angles to equal the sum of a triangle,\n");
System.out.println("this automated program will tell you if the angle you entered is isoceles, eqilateral or scalene");
//creating input 1,2,3 for user
Scanner s = new Scanner(System.in); // Reading from System.in
String line;
int [] angles = new int [3];
int count = 0;
do {
System.out.print("Enter angle degree number " + (count+1) + ": ");
line = s.nextLine();
while (true ) {
try {
angles[count] = Integer.parseInt(line);
System.out.println("You entered " + angles[count]);
count++;
break;
} catch (NumberFormatException e ) {
System.out.println("Invalid number: try again: ");
line = s.nextLine();
}
}
} while (count < 3);
}
}
You have a simple issue.. You just use one Scanner for the code in main method.
package triangle;
import java.util.Scanner;
public class traingle {
public static void main(String[] argc){
System.out.println("You will be able to enter 3 angles to equal the sum of a triangle,\nthis automated program will tell you if the angle you entered is issosoliese, eqilateral or scalene");
Scanner angle1 = new Scanner(System.in);
System.out.println("Enter angle degree number 1: ");
int n = angle1.nextInt();
System.out.println("Enter angle degree number 2: ");
int n2 = angel2.nextInt();
System.out.println("Enter angle degree number 3: ");
int n3 = angel3.nextInt();
Hello guys I am having a problem with an array and a .nextInt(); this is causing my output line at the 3rd prompt to shift up instead of under, and seriously cannot figure out what's wrong.
I have tried .hasNextInt(); but nothing, it actually gives me an error, so here is the code:
import java.util.Random;
import java.util.Scanner;
public class birthday {
public static void main(String[] args) {
System.out.println("Welcome to the birthday problem Simulator\n");
String userAnswer="";
Scanner stdIn = new Scanner(System.in);
do {
int [] userInput = promptAndRead(stdIn); //my problem
double probability = compute(userInput[0], userInput[1]);
// Print results
System.out.println("For a group of " + userInput[1] + " people, the probability");
System.out.print("that two people have the same birthday is\n");
System.out.println(probability);
System.out.print("\nDo you want to run another set of simulations(y/n)? :");
//eat or skip empty line
stdIn.nextLine();
userAnswer = stdIn.nextLine();
} while (userAnswer.equals("y"));
System.out.println("Goodbye!");
stdIn.close();
}
// User input prompt where you make the simulation. For people and return them as an array
public static int[] promptAndRead(Scanner stdIn)
{
System.out.println("Please enter the number of simulations you want to do: ");
int[] userInput =new int [2]; //my problem
userInput[0]= stdIn.nextInt(); //my problem
System.out.println("Please enter the size of the group you want : ");
int[] userInput1 = new int [2];
userInput[1] = stdIn.nextInt();
int a = userInput[1];
while (a<2 || a>365)
{
System.out.println("please type the number that is between 2~365");
}
System.out.println();
return promptAndRead(stdIn);
}
// Method for calculations
public static double compute(int numOfSimulation, int numOfPeople)
{
for (int i =0; i < numOfPeople; i++)
{
Random rnd = new Random(1);
//Generates a random number between 0 and 364 exclusive
int num = rnd.nextInt(364);
System.out.println(num);
System.out.println(num / 365 * numOfPeople * numOfSimulation);
}
return numOfPeople;
}
}
Found it!!!!!!!!!!!
do this:
// User input prompt where you make the simulation. For people and return them as an array
public static int[] promptAndRead(Scanner stdIn)
{
System.out.println("Please enter the number of simulations you want to do: ");
int[] userInput =new int [2]; //CHANGE THIS TO 1?
userInput[0]= stdIn.nextInt(); //my problem
System.out.println("Please enter the size of the group you want : ");
int[] userInput1 = new int [2]; //CHANGE THIS TO 1?
userInput[1] = stdIn.nextInt();
int a = userInput[1];
while (a<2 || a>365)
{
System.out.println("please type the number that is between 2~365");
}
System.out.println();
return(userInput);
}
To return the array
Let me know!
I actually don't think you can do it there with that userInput, I am saying this because the methodology of doing this program is quite arcane.
You are then calling 2 arrays at prompting, I wonder if you might change that to one what will change such as:
// User input prompt where you make the simulation. For people and return them as an array
public static int[] promptAndRead(Scanner stdIn)
{
System.out.println("Please enter the number of simulations you want to do: ");
int[] userInput =new int [2]; //CHANGE THIS TO 1?
userInput[0]= stdIn.nextInt(); //my problem
System.out.println("Please enter the size of the group you want : ");
int[] userInput1 = new int [2]; //CHANGE THIS TO 1?
userInput[1] = stdIn.nextInt();
int a = userInput[1];
while (a<2 || a>365)
{
System.out.println("please type the number that is between 2~365");
}
System.out.println();
return promptAndRead(stdIn);
}
As also the return promptAndRead(stdIn); might be part of the problem
Don't know though just trowing suggestions at Markov ;)