Thread: Math.pow

I'm new to java and trying to be self taught which is proving more and more difficult.

This is the question,

Add an extra CASE that will raise the inputted value to the inputted exponent, using Math.pow (Case E is my extra case)
I truly don't know what its asking for

import java.util.Scanner;
 
public class Arithmetic{
  public static void main(String[] args) {
 
System.out.println("Make your arithmetic selection from the choices below:\n");
 
System.out.println(" A. Addition");
System.out.println(" S. Subtraction");
System.out.println(" M. Multiplication");
System.out.println(" D. Division\n");
 
System.out.print(" Your choice? ");
 
Scanner kbReader = new Scanner(System.in);
String choice = kbReader.nextLine( );
//char ch = choice; //You would think this would work…but it doesn’t.
char ch = choice.charAt(0); //you just learned another String method.
 
System.out.print("\nEnter first operand. " );
double op1 = kbReader.nextDouble( );
System.out.print("\nEnter second operand." );
double op2 = kbReader.nextDouble( );
 
System.out.println(" ");
 
switch (ch)
{
	case 'A': //addition
	case 'a': //Notice we are providing for both capital A and little a.
	   System.out.println(op1 + " plus " + op2 + " = " + (op1 + op2) );
           break;
	case 'S': //subtraction
	case 's':
	    System.out.println(op1 + " minus " + op2 + " = " + (op1 - op2) );
            break;
	case 'M': //multiplication
	case 'm':
	    System.out.println(op1 + " times " + op2 + " = " + (op1 * op2) );
            break;
	case 'D': //division
	case 'd':
	    System.out.println(op1 + " divided by " + op2 + " = " + (op1 / op2) );
            break;
        case 'E': // Math.pow
        case 'e':
            System.out.println("pow(" + op1 + ", " + op2 + ") is " + Math.pow(op1, op2));
            break;
        default:
	    System.out.println("Hey dummy, enter only a A, S, M, or D!");
  }
 }
}

I truly don't know what its asking for

Can you explain the problem? Are you getting error messages? Please copy and paste the full text here.

Please Edit your post and wrap your code with
[code=java]
<YOUR CODE HERE>
[/code]
to get highlighting and preserve formatting.

Its not giving me anything when I run the program.

Can you post the contents of the console window that shows what you are talking about?

On windows: To copy the contents of the command prompt window:
Click on Icon in upper left corner
Select Edit
Select 'Select All' - The selection will show
Click in upper left again
Select Edit and click 'Copy'

Paste here.

Can you explain what is wrong with what the program did when you executed it?
The output looks like the program did what it was supposed to do.

If you take out the case for M, S or D you will also get the same thing when you enter an 'a'. The code for those other letters is not being used when you enter an 'a'.

Try entering an e (instead of the a) when the program asks you for your selection. The program will not use the case 'E' unless you enter an 'e'.

Can you explain the problem?

This is what I'm getting. This is from the Blue Pelican java book online and since I didn't buy the answers, I have no way of checking to see what's wrong.

C:\myJava>javac Password.java
Password.java:17: error: cannot find symbol
if (thePassword = XRay)
^
symbol: variable XRay
location: class Password
Password.java:17: error: incompatible types
if (thePassword = XRay)
^
required: boolean
found: int
2 errors

C:\myJava>

I'm sure its looking for integers (int)

You are using the assignment operator (=) instead of the comparsion operator (==).
The value returned by an assignment is what is to the left of the =.
An if statement requires a boolean value, not an int

required: boolean
found: int

Take a look at these:
Equality, Relational, and Conditional Operators (The Java™ Tutorials > Learning the Java Language > Language Basics)
The if-then and if-then-else Statements (The Java™ Tutorials > Learning the Java Language > Language Basics)

Is Xray the name of a variable? If so you need to define it and give it a value.
Or did you want it to be a String? If so enclose it in "s.

The last line of your post encloses the s in "s "s"

This line defines the variable: thePassword as a boolean variable

boolean thePassword

What text are you using to learn java? These questions should be covered in the first chapter.

Take a look through the tutorial:
http://docs.oracle.com/javase/tutorial/java/TOC.html

still getting the same error.

If you had made either of the changes you should get a different error.
Please post the new code and the full text of the error messages.

Where is the variable named: Xray defined? The compiler can not find its definition.

Where is the variable named: Xray defined? The compiler can not find its definition.
Also see post #16