Class #4 - 01/21/2010/Thursday
NetLogo turtle graphics lab session


  1. Group Exercise from Tuesday, January 19th - The final exam from Fall 2009 started with these two questions. The questions ask you to show what the output would look like from a fairly simple NetLogo program by drawing where the turtles end up and drawing where the turtles left trails, drawing something on the grid when their PD Pens were Down and they moved. The solution to this is available below here in the link from item two to a NetLogo application that demonstrates the output using a checkered grid, so its easy to see the 17 by 17 squares in the NetLogo world.
  2. See the solution to Tuesday's group exercise questions by using this NetLogo application. The GRID is exactly the same size as the two final exam test questions, but I have colored the grid like a checkerboard so that you can see the PATCHES and count how many steps the turtles took and so on.
  3. Music and NetLogo : singing or rather playing the Happy Birthday song with a Trumpet.
  4. Turtles can be different shapes.
    1. ask turtles [ set shape one-of shapes ] will choose a random shape for each turtle.
    2. show shapes wil give a list of all the available shapes that you have to choose from when using NetLogo.
    3. ask turtles [ set shape "fish" ] will have all turtles change to the specific shape you request, such as the FISH shape requested here.
    4. LIST of TURTLE shapes: ["default" "airplane" "arrow" "box" "bug" "butterfly" "car" "circle" "circle 2" "cow" "cylinder" "dot" "face happy" "face neutral" "face sad" "fish" "flag" "flower" "house" "leaf" "line" "line half" "pentagon" "person" "plant" "square" "square 2" "star" "target" "tree" "triangle" "triangle 2" "truck" "turtle" "wheel" "x"]
    5. Random Shapes via set shape one-of shapes... Each circle of turtles has fewer turtles, so the outermost turtles have lots more turtles than the innermost circle.
    6. More Randomly Shaped turtles. There are 16 spokes here. Each spoke is the same color, but is made up of different shapes.
    7. Fish making up 12 spokes illustrating the [ SET SHAPE "fish" ] statement the turtles were asked to do.

  5. ... more here later ...
  6. ... check back AFTER the 4th class is done and BEFORE the 5th class ...
  7. The concept of Emerging Order is explained here in this NetLogo introduction from Evergreen State College in Olympia, Washington. Great overview of NetLogo and how it can be used and why its a good tool for computer modeling and simulation.