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Mobius strip

Assignment 5


Create a ComplexNumber class, which will be capable of graphically plotting each number on a coordinate plane.



Create your project in Eclipse, and then import the new version of wheels: coordwheels.jar. (This version also includes the source code.)

The only difference in the new wheels is that I have extended the Frame class so that it displays an x and y-axis and plots shapes relative to the center of the screen. So, you will be able to draw lines as you did in Assignment 2; however, you must create a CoordinateFrame object rather than a Frame object before you start drawing. (This will be done as a static member of ComplexNumber.)

(There is also slight hiccup in that you may need to call repaint() on CoordinateFrame after you finish drawing to get the shapes to render properly without having to minimize the window first.)

Write a ComplexNumber class that includes the following details:

Static variables (protected):

  • CoordinateFrame display = new CoordinateFrame(); -- from wheels.users

Instance variables (private):

  • double real
  • double imaginary
  • Color color -- this a java.awt.Color

Constructor (public):

  • ComplexNumber(double real, double imaginary) -- Should construct the given ComplexNumber, setting its color to

Methods (public):

  • String toString() -- Returns a string of the form "real + imaginaryi".
  • Color getColor()
  • void setColor(Color c)
  • void draw() -- Will draw a line from the origin (0,0) to this ComplexNumber (real, imaginary) in this number's current color.
  • void drawFrom(ComplexNumber source) -- Will draw a line from the given source point to this number, using this number's color.

Remember, you may have to call display.repaint() at the end of your draw methods.

Now, to test the new ComplexNumber class, write a main method in the ComplexNumber class. In this method, you should:

  • Create a couple complex numbers. This should produce a CoordinateFrame on the screen with gray coordinates already drawn on it.
  • Call the draw methods of the numbers you created, and they should show up on the frame.
  • Test your other methods.

For the first time, I will be enforcing coding standards, so be sure to format and document your code properly.

If written correctly, your ComplexNumber class will work with my If you get any compile errors, fix your ComplexNumber class to match the specifications above. Plotter is a short little program that prompts for a series of ComplexNumber coordinates and draws them.

What to Submit

Attach your file to an email.


Example code from lab?
Right here:


Out of 10 points:

1 - Submission
Follows required submission policies.
2 - Coding Standards
1 - Correct constructor
3 - Correct methods
toString and color methods each worth 0.5 points.
1 - Main method as described
Draws at least a couple complex numbers on the frame.
2 - Plotter compiles and runs correctly using your ComplexNumber.


~ztomasze Index : TA Details: ICS111: Assignment 5
Last Edited: 05 Oct 2007
©2007 by Z. Tomaszewski.