Codr101

/* 
 * File: metricToO.java
 * Solution for: The Art and Science of Java by Eric Roberts - Chapter 3 Exercise 6
 * ---------------------
 * The user can input a weight in kilograms.
 * The application then displays the corresponding weight in pounds and in ounches.
 */

package com.aus.ch3.solutions;

import acm.program.ConsoleProgram;

public class MetricToOunces_7 extends ConsoleProgram {

	public void run(){
		setSize(400, 150);
		
		println("This application converts metric weight from kilograms to pounds and ounces");
		double kilo = readDouble("Enter weight in kilo: ");
		double pounds = toPounds(kilo);
		double ounches = toOunches(kilo);
		println(kilo + " kilograms are equal to " + pounds + " pounds" );
		println(kilo + " kilograms are equal to " + ounches + " ounches " );
	}

	/**
 * converts from kilograms to ounches
 * 
 * @param kilo weight in kilograms
 * @return weight in ounches
 */
	private double toOunches(double kilo) {
		double ounches = kilo * 16;
		return ounches;
	}

	/**
 * converts from kilograms to pounds
 * 
 * @param kilo weight in kilograms
 * @return weight in pounds
 */
	private double toPounds(double kilo) {
		double pounds = kilo * 2.2;
		return pounds;
	}
}

/*
 * File: MilosCalculations_6.java
 * Solution for: The Art and Science of Java by Eric Roberts - Chapter 3 Exercise 6
 * ---------------------
 * The application displays Milos calculations from the Book "The Phantom Tollbooth"
 * according to Milos calculations the calculation work out to zero.
 * The actual solution differs from the one the application gives, using
 * the java precedence rules 
 */

package com.aus.ch3.solutions;

import acm.program.ConsoleProgram;

public class MilosCalculations_6 extends ConsoleProgram {

	public void run(){
		setSize(300 , 100);
		
		double intValues = 4 + 9 - 2 * 16 + 1 / 3 * 6 - 67 + 8 * 2 - 3 + 26 - 1 / 34 + 3 / 7 + 2 - 5;
		println("int values: " + intValues);
		double doubleValues = 4.0 + 9.0 - 2.0 * 16.0 + 1.0 / 3.0 * 6.0 - 67.0 + 8.0 * 2.0 - 3.0 + 26.0 - 1.0 / 34.0 + 3.0 / 7.0 + 2.0 - 5.0;
		println("double values: " + doubleValues);
	}
}

/*
 * File: FahrenheitToCelsius_5.java
 * Solution for: The Art and Science of Java by Eric Roberts - Chapter 3 Exercise 5
 * ---------------------
 * The user can input the temperatur in degrees Fahrenheit.
 * The application will then display the corresponding value
 * in degrees Celsius.
 */

package com.aus.ch3.solutions;

import acm.program.ConsoleProgram;

public class FahrenheitToCelsius_5 extends ConsoleProgram {

	public void run(){
		setSize(400, 200);
		
		println("This application converts Fahrenheit to Celsius");
		double fahrenheit = readDouble("Enter Fahrenheit: ");
		double celsius = toCelsius(fahrenheit);
		println("Celsius equivalent: " + celsius);
	}

	/**
 * converts fahrenheit to celsius
 * 
 * @param fahrenheit the temperature in degrees fahrenheit
 * @return the temperature in degrees celsius
 */
	private double toCelsius(double fahrenheit) {
		double celsius = (5/9.0) * ( fahrenheit - 32 );
		return celsius;
	}
}

/*
 * File: CircleArea_4.java
 * Solution for: The Art and Science of Java by Eric Roberts - Chapter 3 Exercise 4
 * ---------------------
 * The user can input the radius of a circle and the application then
 * computes the area
 */

package com.aus.ch3.solutions;

import acm.program.ConsoleProgram;

public class CircleArea_4 extends ConsoleProgram {

	public void run(){
		setSize( 400, 200);
		
		println("This application will calculate the area of a circle");
		double radius = readDouble("Enter the radius of the circle in Cm: ");
		double circleArea = circleArea(radius);
		println("The radius is: " + circleArea + "Cms^2");
	}
	/**
 * calculates the area of a circle
 * 
 * @param radius the radius of the circle
 * @return the area of the circle
 */
	private double circleArea(double radius) {
		double circleArea = Math.PI * Math.pow(radius, 2);
		return circleArea;
	}
}

/*
 * File: Interest_2.java
 * Solution for: The Art and Science of Java by Eric Roberts - Chapter 3 Exercise 2
 * ---------------------
 * This application calculates the account balance for any number of years bases on
 * data the user inputs like: start balance, interest rate, and the years of interest.
 * 
 * The application assumes that there are no depositions or withdrawals made.
 */

package com.aus.ch3.solutions;

import acm.program.ConsoleProgram;

public class Interest_2 extends ConsoleProgram {

	public void run() {
		setSize(400, 200);

		println("Interest calculation Program");
		double start = readDouble("Enter starting balance: ");
		double interest = readDouble("Enter anual interest rate: ");
		int years = readInt("Enter years to calculate interest: ");

		double balance = start;

		for (int i = 0; i < years; i++) {
			balance = compute(balance, interest);
			int printyear = i + 1;
			println("Balance after year " + printyear + ": " + balance);
		}
	}

	/**
 * calculates the balance for the next year
 * 
 * @param start
 * the balance to start the computation (balance at january of
 * the year)
 * @param interest
 * at which rate the interest is calculated
 * @return balance after one year
 */
	private double compute(double start, double interest) {
		double balance = start * (1 + (interest / 100));
		return balance;
	}
}