[an error occurred while processing this directive] CMSC 202 - Fall 2013 - Lab 3

Creating the decimalValue method

Overview

Description

  1. Starting Eclipse
  2. Creating the Fraction and FractionDriver Classes
  3. Creating Instance Variables, a Constructor, Accessors, and Mutators
  4. Creating the toString Method
  5. Creating the decimalValue Method
  6. Creating the multiply Method
  7. Creating the equals Method

For our Fraction class, it would be nice to have a method for converting a Fraction to a single primitive value. This is an easy computation which will result in a floating point or double number.

The decimal value of the fraction can be obtained by dividing a Fraction's numerator by its denominator.

Java considers a division operation as double or integer division based on the following rules:

  1. If both the operands are integers then integer division is performed.

    Integer division gives the quotient(integer) of the division and the remainder of the division is ignored/lost.

    For example 12/5 is 2

  2. If one of the operands is float or double then the division performed is double division and the result is a double value.

    For example 12.0/5 is 2.4

Double division needs to be performed to get a decimal value. The following example casts both values to doubles, but it would be sufficient to only cast one value to a double as division between an int and a double in Java results in a double. 

/**
 * Returns the decimal value of the Fraction
 * Precondition: None
 * Postcondition: None
 * @param None
 * @return A double representing the decimal value of this Fraction
 */
public double decimalValue()
{
  //Explicitly change the data type of numerator and denominator. Eg. (double)var;
  //return the decimal value by dividing the numerator and denominator, both converted to double
}

Testing

  1. Un-comment the code in main that prints the decimal value of the two fractions.
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