UCSC: Porter 34B, Chaos, Fractals, and the Arts, Winter 2015

Homework 04. Assigned Friday January 30, 9:30 am

Due via email to abraham@vismath.org, Wednesday February 04, by 8 am.

A. Read "The Cosmic Cinema of Jordan Belson", [ Gene Youngblood ].

There may well be a short quiz on this in Meeting #5.

B. Locate a periodic window in the KKM family. (Improved from HW 03)

#1. Download the NetLogo model, mira3.nlogo.

This has been improved and simplified from mira2.nlogo.

#2.: Use the model to find values of the parameter "a" and "b" sliders with periodic behavior.

• 2.1 Fix the "a" slider to "0.7" and leave it there
• 2.2 Adjust the "b" slider to a value between "-1.0" and "-0.4"
• 2.3 Click the "setup" button
• 2.4 Click "go" to start, and quickly click it again to stop the model
  (OR, click "go-100" several times)
• 2.5 Click the "paint-hits" button to color the patches that have been hit
• 2.6 Click the "clear" button
• Repeat steps 2.4 and 2.5
• You are looking for a screen that is nearly all black, indicating periodic behavior
• 2.6. Use the "step" button to count to determine the period
• Repeat from 2.2 to 2.6 in several experiments
• I will not post a tutorial video for this process unless it proves necessary

#3. Report the approximate values of "b" and the corresponding periods in your email to me.

C. Learning NetLogo. (Repeat from HW 03)

Look up the definition of "reporter".

#1. Create a simple turtle model from scratch (OK to use junk.nlogo.)

#2. Include at leasts one reporter in your model, and use it in a button procedure.

HINT: Do not try to attach your reporter directly to a button.

Use it inside a new procedure, and attach that procedure to a new button.

#3. Send me your model "hw4.nlogo" as an attachment to your email (not a txt file).