How do you compile the simple calculator in java?

Answer 1

Here is a calculator program I had to make in my Computer class in bluej (free java compiler)

import java.io.*;

import java.util.*;

public class Calculator

{

public static void main(String args[])

{

System.out.println("Make your arithmetic selection from the choices below:\n");

System.out.println(" 1. Addition");

System.out.println(" 2. Subtraction");

System.out.println(" 3. Multiplication");

System.out.println(" 4. Division\n");

System.out.print(" Your choice? ");

Scanner kbReader = new Scanner(System.in);

int choice = kbReader.nextInt();

if((choice<=4) && (choice>0))

{

System.out.print("\nEnter first operand. ");

double op1 = kbReader.nextDouble();

System.out.print("\nEnter second operand.");

double op2 = kbReader.nextDouble();

System.out.println("");

switch (choice)

{

case 1: //addition

System.out.println(op1 + " plus " + op2 + " = " + (op1 + op2) );

break;

case 2: //subtraction

System.out.println(op1 + " minus " + op2 + " = " + (op1 - op2) );

break;

case 3: //multiplication

System.out.println(op1 + " times " + op2 + " = " + (op1 * op2) );

break;

case 4: //division

System.out.println(op1 + " divided by " + op2 + " = " + (op1 / op2) );

}

}

else

{

System.out.println("Please enter a 1, 2, 3, or 4.");

}

}

}

Answer 2

// Program for simple calculator

public class Calc

{

public static void main(String args[])

{

int x,w,z;

char y;

if(args[]!=3)

{

System.out.println("Wrong Syntax");

System.out.println("NOTE: Please compile like this");

System.out.println("c:\java\jdk1.6\javac Calc 25 + 3 ");

System.out.println("c:\java\jdk1.6\javac Calc 25 - 3 ");

System.out.println("c:\java\jdk1.6\javac Calc 25 x 3 ");

System.out.println("c:\java\jdk1.6\javac Calc 25 / 3 ");

System.out.println("c:\java\jdk1.6\javac Calc 25 % 3 ");

System.exit(0);

}

x= Integer.parseInt(args[0]);

y= Character.parseChar(args[1]);

z= Integer.parseInt(args[2]);

switch(y)

{

case '+' : w=x+z;

System.out.println("Addition = "+w);

break;

case '-' : w=x-z;

System.out.println("Substraction = "+w);

break;

case 'x' :

case 'X' : w=x*z;

System.out.println("Multiplication = "+w);

break;

case '/' : w=x/z;

System.out.println("Division = "+w);

break;

case '%' : w=x%z;

System.out.println("Modulus = "+w);

break;

}

}

}

Answer 3

You can use the built-in methods of the java Math class to do the actual calculations. If you are supposed to do this yourself, rather than using available components, you can use the infinite series expansion (Taylor series) which you can find online in many places. For example:

sin(x) = x - x3/3! + x5/5! - x7/7! + x9/9! ...

Although in theory the series is infinite, in practice you'll continue adding terms until the current term becomes less than some threshold value, depending on the desired accuracy. Or rather, the absolute value of the term.

5!, for example, means 5!, in other words, 1 x 2 x 3 x 4 x 5. Note that the angle must be in radians. If the angle is in degrees, you must convert to radians first. This applies to the built-in methods of the Math class as well.

The Wikipedia article "Taylor series" contains the infinite series for other trigonometric functions. Some of these are too complicated, in my opinion; for example, to calculate tan(x), it is more convenient to use the identity tan(x) = sin(x) / cos(x), and re-use the sin() and cos() methods instead. Also, sec(x) = 1 / cos(x), csc(x) = 1 / sin(x), and cot(x) = 1 / tan(x).