The Journal of Online Mathematics and Its Applications, Volume 8 (2008)
Modeling Spiral Growth in a GSP Environment, Dogan-Dunlap and Jordan

How to Run GSP Program

Make sure you are familiar with the basics of GSP, and the Spirals.gsp file before beginning the procedure to be provided next. By entering different values for the parameter n, the program will generate different types of spirals or/and rays. Now, open the file Spirals.gsp.

The detailed procedure is as follows:

  1. To reset the incrementing parameter k, double click on the parameter k object. The dialog box in Figure 1 will appear.

    Figure 1. Resetting the seed number parameter.

  2. Clear the current value, and enter 1 to start the process from the first seed (point).
  3. To clear the previous plotted points/spirals (and any other traces that may be on the page), select Erase Traces from the Display menu.
  4. To enter a new value for parameter n, right click on the parameter n object, and select Edit Calculation. The dialog box in Figure 2 will appear.
  5. Enter the desired value for n. Click OK. (Note: n along with k determines the position where each sequential seed of the spirals or rays will appear).

    Figure 2. Enter new value for the parameter n.

  6. To animate the incrementing parameter k, right click on the parameter k object. Select Animate Parameter from the menu. The dialog box in Figure 3 will appear (If the animation dialog box does not appear, go to the Display menu, and select Resume Animation option). Make sure no other object is highlighted.
  7. At the current setting, one seed per second is generated. You may want to increase the speed to generate the seeds faster.
  8. To stop the Animation process, press the stop button on the Motion Controller dialog box.

    Figure 3. Motion Controller Dialog Box.

  9. You can repeat steps 1-8 for each new value of n.
  10. You can hide the grid from the Graph menu in order to have a clearer view of the spirals/rays.
  11. The axes can also be hidden by highlighting them, and using the Display menu.