GeoCalc

Overview

For this activity you will complete the implementation of a GEOmetric CALCulator. The calculator lets you create simple geometric objects - lines, rectangles, and circles - from points in the Point class presented in class. Once created, the objects can be queried for various properties: lines can compute their length; rectangles can compute their height, width, perimeter, and area; circles can compute their radius, diameter, circumference and area. A driver program - geocalc.rb - reads commands from standard input (either the keyboard or a file using input redirection), creates geometric objects using the command parameters, and prints out information on the resulting object.

Preparation

1. Create a directory GeoCalc at the top level of your GIT workspace for this course.
2. Download the ActivityJournal.txt
3. Download the geocalc.zip archive and extract its contents into the GeoCalc directory. A directory listing should show the following files:

circle.rb

Defines the Circle class, which depends on (requires) the Point class. The requires './point' loads point.rb from the current directory and makes it available to the body of circle.rb. You will have to complete code for this class.

geocalc.rb

Contains the basic command interpreter - since it uses all the classes in the system it has a long sequence of requires statements at the head of the file.
This file is complete - there is nothing you must add or modify within it. The supported commands are discussed in Activities below.

line.rb

Defines the Line class, which, like Circle, depends on Point. You will have to complete code for this class.

point.rb

Defines the Point class. For our purposes the definition is complete; there is nothing you need add or modify in this file.

rectangle.rb

Defines the Rectangle class, which, like Line and Circle, depends on Point. You will have to complete code for this class.

4. Before proceeding to the activities, we strongly suggest you scan all the Ruby source files to get "a feel" for how all the pieces fit together. Feel free to ask your instructor or student course assistant for help.
5. Start your Activity Journal.
6. To run the program at any time, type the following at the command prompt:
   
   ruby geocalc.rb
   
   and enter commands via the keyboard. On hamilton, typing CTRL+D at the start of a line will exit the program. You can also put a sequence of commands in a file, say commands.txt, and use redirection to run the tests without typing them again and again:
   
   ruby geocalc.rb < commands.txt

Activities

1. Complete and test (creating a line_test.rb unit test file) the Line class in line.rb. This is the simplest of the classes.
2. Complete and test  (creating a circle_test.rb unit test file) the Circle class in circle.rb. This is a tad more challenging that Line.
3. Complete and test (creating a rectangle_test.rb unit test file) the Rectangle class in rectangle.rb. While this may appear simpler than Circle, it is set up so you have to do more of the work.

Submission