Net Logo Uri Wilensky Tutorial by BinTzong Chie

Net. Logo Uri Wilensky Tutorial by Bin-Tzong Chie AI-Econ Research Center, National Chengchi University Department of Industrial Economics, Tamkang University

Outline • • Introduction Build a Model Applets Hub. Net

Net. Logo • Net. Logo is a programmable modeling environment for simulating natural and social phenomena. It was authored by Uri Wilensky in 1999 and is in continuous development at the Center for Connected Learning and Computer-Based Modeling. • More Information – http: //ccl. northwestern. edu/netlogo/docs/

Download and Install • http: //ccl. northwestern. edu/netlogo/

Initial the Net. Logo

Exemplify a Model

Example of El Farol Problem

Three Main Tabs of a Model • Interface Tab • Information Tab • Procedure Tab

Interface Tab World The Interface

The World Setting

Information Tab

Procedure Tab

Initial the Model

Run the Model

How does the Model work? • Global Variables • Agent’s Variables • Defined Procedures – Linked with Interface – Sub procedure • Without return values • With return values

Global Variables globals [ attendance history home-patches bar-patches crowded-patch ] ; ; ; ; ; the current attendance at the bar list of past values of attendance agentset of green patches agentset of blue patches patch where we show the "CROWDED" label

Agent’s Variables turtles-own [ strategies best-strategy attend? prediction ] ; ; ; ; list of strategies index of the current best strategy true if the agent currently plans to attend the bar current prediction of the bar attendance

Procedures Linked with Interface to setup. . . end Event Trigger to go. . . end

Procedures as Sub-Procedures without return values to move-to-empty-one-of. . . end to update-plots. . . end to update-strategies. . . end

Procedures as Sub-Procedures with return values to-report predict-attendance. . . report. . . end to-report random-strategy. . . report. . . end

Let’s Play

Instance Interactive with the agents

Stalk an Agent

Save as Applet

Hub. Net

How to apply Hub. Net to startup setup hubnet-set-client-interface "COMPUTER" [] hubnet-reset end to go every 0. 1 [ listen-clients display ] end

to listen-clients ; ; as long as there are more messages from the clients ; ; keep processing them. while [ hubnet-message-waiting? ] [ ; ; get the first message in the queue hubnet-fetch-message ifelse hubnet-enter-message? ; ; when clients enter we get a special message [ create-new-student ] [ ifelse hubnet-exit-message? ; ; when clients exit we get a special message [ remove-student ] [ ask students with [user-id = hubnet-message-source] [ execute-command hubnet-message-tag ] ; ; otherwise the message means that the user has ] ; ; done something in the interface hubnet-message-tag ; ; is the name of the widget that was changed ] ] end

Hub. Net Client Editor

Do you want to go to the Bar