So I need to make a for loop for this problem: A certain type of bacteria doubles its population every twelve hours. If you start with a population of 1000, how many hours will it take for the population to exceed 1,000,000? Output needs to be in table format, such as:
I'm having an issue with figuring out how to structure and call a method using a string prompt. My prof has given us specific methods to create, and the one I'm having issues with is blic static double getOperand(String prompt). What I have currently is this:
public static double getOperand(String operand1, String operand2){ Scanner input = new Scanner(System.in); System.out.println("What is the first operand?"); operand1 = input.toString();
System.out.println("What is the second operand?"); operand2 = input.toString(); return operand1, operand2; }
which is obviously not working. When I asked my prof he sent me this, "The String paramater in the getOperand() method is intended to have the prompt value that is passed to it. Within the method, the prompt is then displayed, what the prompt is asking for is input, and then returned to the method call.For example, if the method is public double getOperand(String prompt) within the method you would display the prompt, as in System. out. println(prompt), use the Scanner class to create an object, perhaps called input, and then use the input object to get the value asked for by the prompt. Once you have that value, which in this example would be a double, then return the value to the method that called it.
The call could be something like this: double value = getOperand("What is the first operand?");". But that only works a little. Clearly I'm missing something and no matter what I google, or how many times I read the chapter, I am just not getting this. Everything else up to this point has been easy. and I can create regular methods just fine, the menu method works, but I can't figure out this string method and all the rest build off this method.
I am writing a program where I need to split an array of full names into First names and Surnames, using mapping. However, I am struggling how to split it up... and my First Names and Surnames list are both just displaying the full name.
public static void main(String[] args) { String[] names; names = new String[8]; Scanner s = new Scanner(System.in); for (int i = 0; i < names.length; i++) { System.out.println("Enter full student name:");
I am currently trying to split the string "EAM est" between the part. I have gotten the code to work if the was a -. But I can't see why the error is occuring
I am trying to split a string into a String[] tokens array to declare variables for an object; however, I'm having an issue getting the string to tokenize correctly. Here's an example of the input:
a : 100 : John Smith : 20 Main St. a : 101 : Mary Jones : 32 Brook Rd.
Here is the basic code I have now, to properly sort each line of text, etc. (without the split() method):
Java Code:
while (scanner.hasNextLine()) { currentLine = scanner.nextLine(); lineScan = new Scanner(currentLine); if (currentLine.startsWith("/") || currentLine.trim().isEmpty()) continue;
[Code] ....
I was able to eliminate the comments and identifiers from the text by trimming the first two characters of the string. For the split, I tried String[] tempArray = currentLine.split("s+"); however, that also took the spaces out of the addresses and names...so the results looked like this:
100 John Smith 20 Main St.
As you can see, it splits via space regardless, including where I replaced all the :'s with spaces. Is there any way to do this?
I've written a program just for the sake of it (to learn) and it seem's like theres quite a lot in the main method that perhaps could be split up into seperate classes. I'm not too sure where should start with this though, or what my thought process should have been as I was writing the program.
import java.util.Scanner; public class Loops { public static void main(String[] args) { int answer = 16; Scanner scan = new Scanner(System.in); // Question System.out.println("What is 4 x 4 ?");
[code]...
--- Update ---
here's a version without code comments as they might make it harder to read here -
import java.util.Scanner; public class Loops { public static void main(String[] args) { int answer = 16; Scanner scan = new Scanner(System.in); System.out.println("What is 4 x 4 ?"); int userAnswerInt = 0;
I am trying to run a class with a client code and I get the following error
The method add(TimeSpan) is undefined for the type TEST
Why i get this error?
package timespan; // Represents a time span of hours and minutes elapsed. // Class invariant: minutes < 60 public class TimeSpan { private int hours; private int minutes;
I have an requirement of splitting a Date-Time String i.e. 2013/07/26 07:05:36 As you observe the above string has Date and Time with space in between them.
Now I want just want split the string not by delimiter but by length i.e. after 10th place and then assign it to 2 variable i.e. Date <----2013/07/26 and Time <---07:05:36 separately.
I am trying to convert the double 4270571936.0000000000d to a hex string using Double.toHexString() and the answer I'm getting is 0x1.fd17834p31, what does p stands for?
The answer I'm expecting to get is 0x41efd17834000000 so not sure why it won't give me the correct answer?
The following floating point Double to hex calculator shows the write answer right Floating Point to Hex Converter
//Students Full Name firstName = JOptionPane.showInputDialog("Enter student " + "first name."); lastName = JOptionPane.showInputDialog("Enter student " + "last name."); // Get test grade (numbers) [b]test1 = JOptionPane.showInputDialog("Enter test1 grade")[/b];
The line in bold is where that error comes up. I know it something simple but I can't remember. I declared both firstName and lastName as Strings and then the test1 I declared as double. I had a similar error in a previous assignment where I had a integer(age) input and then i had an output statement asking for a name all I needed to do was put keyboard.nextLine(); after my age input and I was fine.
I am making a program where the user types in how many students, the student name and the student result. My problem is typing in a dobule name for instance: Tom Tom.
I have tried both:
String name = input.Next(); -> Only works with one name. and String name = input.nextLine(); -> Skips right trough and ask me to type result again.
Here is my code:
Java Code:
import java.util.Scanner; public class c5e8 { public static void main(String[]args){ Scanner input = new Scanner (System.in); int highestResult = 0; String highestName = " ";
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)
I've a question on rounding doubles on 0.05 As far as i know there is no class method that is able to do this. To achieve this rounding i have the following code:
This may be a multipart question. Basically I have to write a program that accepts a string, converts it to a double splits it and then performs a calculation.
public static void main(String[] args) { String input = ""; // initalize the string boolean isOn = true; // used for the while loop...when false, the program will exit. String exitCommand = "Exit"; // exit command String[] token = input.split(("(?<=[-+*/])|(?=[-+*/])"));
[Code] ....
This is the error I get:
Enter a math problemException in thread "main" java.lang.NumberFormatException: empty String at sun.misc.FloatingDecimal.readJavaFormatString(Floa tingDecimal.java:1842) at sun.misc.FloatingDecimal.parseDouble(FloatingDecim al.java:110) at java.lang.Double.parseDouble(Double.java:538) at Calculator.main(Calculator.java:22)
[Code] .....
How do I go about actually fixing it. Without that line commented out I get this:
Enter a math problem 2+2 <-What I entered [Ljava.lang.String;@135fbaa4
Also, how would I go about using the submethods to check for valid operands and operators (also part of the problem) I have the actual lists made obviously, but am unsure how to get those to work with the problem.
I have a double primitive and gave it a huge value. I am curious if valueOf could ever potentially cause data loss. I tried a simple test and it seems it never loses any data:
Java Code:
public class DoubleStringTest { public static void main(String[] args) { double val = 1029.129348558634; System.out.println(val); System.out.println(String.valueOf(val)); } } mh_sh_highlight_all('java');
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 am working with java project which is kind of charting room..but the problem is when am writing the query for listing the message in the conversation the error prevail in my eclipse...string literal is not properly closed by double quote...this is my java file
I am working on a project that just calculates simple interest based upon a principal and a percent interest rate written as .xxxx from user.
I need the Loan amount and the final interest calculation to show up as a currency with commas in appropriate areas, the Rate to be expressed as X.xxx% instead of .xxxx
I keep getting this error when I compile:
C:JavaInterestCalculator.java:46: error: incompatible types: String cannot be converted to double principal = formatter.format(principal); ^ C:JavaInterestCalculator.java:49: error: incompatible types: String cannot be converted to double rate = formatter.format(rate); ^ C:JavaInterestCalculator.java:52: error: incompatible types: String cannot be converted to double totalInterest = formatter.format(totalInterest); ^ 3 errors
Tool completed with exit code 1
And here is my code
import java.util.Scanner; import java.text.NumberFormat; import java.text.DecimalFormat; // class declaration public class InterestCalculator { // main method declaration
