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<!-- need explicit head tag, otherwise htmldoc thinks the stuff inside
the style tags is in the body -->
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01//EN"
"http://www.w3.org/TR/html4/strict.dtd">
<title>
NetLogo User Manual: NetLogo Dictionary
</title>
<link rel="stylesheet" href="netlogo.css" type="text/css">
<meta http-equiv="Content-Type" content="text/html; charset=us-ascii">
<style type="text/css">
p { margin-left: 1.5em ; }
h3 { font-size: 115% ; }
h4 { font-size: 100% ; margin-left: 1.5em ; background: white ; }
</style>
<h1>
NetLogo Dictionary
</h1>
<div class="version">
NetLogo User Manual
</div>
<table border="1" align="center">
<tr>
<td>
<font size="-1">Alphabetical: <b><a href="#A">A</a> <a href=
"#B">B</a> <a href="#C">C</a> <a href="#D">D</a> <a href=
"#E">E</a> <a href="#F">F</a> <a href="#G">G</a> <a href=
"#H">H</a> <a href="#I">I</a> <a href="#J">J</a>
<!--<a href="#K">K</a>-->
<a href="#L">L</a> <a href="#M">M</a> <a href="#N">N</a>
<a href="#O">O</a> <a href="#P">P</a> <!--<a href="#Q">Q</a>-->
<a href="#R">R</a> <a href="#S">S</a> <a href="#T">T</a>
<a href="#U">U</a> <a href="#V">V</a> <a href="#W">W</a> <a href=
"#X">X</a> <a href="#Y">Y</a> <!--<a href="#Z">Z</a>-->
<a href="#ops">?</a></b></font>
</table>
<table border="1" align="center" cellpadding="3">
<tr>
<td>
<div align="center">
<font size="-1">Categories: <a href="#turtlegroup">Turtle</a> -
<a href="#patchgroup">Patch</a> - <a href=
"#agentsetgroup">Agentset</a> - <a href="#colorgroup">Color</a>
- <a href="#taskgroup">Task</a> - <a href=
"#controlgroup">Control/Logic</a> - <a href=
"#worldgroup">World</a> - <a href=
"#perspectivegroup">Perspective</a>
<br>
<a href="#iogroup">Input/Output</a> - <a href=
"#fileiogroup">File</a> - <a href="#listsgroup">List</a> -
<a href="#stringgroup">String</a> - <a href=
"#mathematicalgroup">Math</a> - <a href=
"#plottinggroup">Plotting</a> - <a href="#linkgroup">Links</a>
- <a href="#moviegroup">Movie</a> - <a href=
"#systemgroup">System</a> - <a href=
"#hubnetgroup">HubNet</a></font>
</div>
</table>
<table border="1" align="center" cellpadding="3">
<tr>
<td>
<font size="-1">Special: <a href=
"#builtinvariables">Variables</a> - <a href=
"#Keywords">Keywords</a> - <a href=
"#Constants">Constants</a></font>
</table><!--
NOTE!
The reason the h2 headers have an extra in them, like this:
<h2><a name="A">A </a></h2>
instead of just:
<h2><a name="A">A</a></h2>
is to work around an extremely obscure bug in Internet Explorer
where without the extra stuff, some of the links from primitives.html
don't always work on every computer. (On one computer it was just
the "I" link that didn't work; on other computers it was more.)
Go figure! - ST 12/2/04
-->
<h2>
Categories
</h2>
<p>
This is an approximate grouping. Remember that a turtle-related
primitive might still be used by patches or the observer, and vice
versa. To see which agents (turtles, patches, links, observer) can
actually run a primitive, consult its dictionary entry.
<!-- ======================================== -->
<h3>
<a name="turtlegroup" id="turtlegroup">Turtle-related</a>
</h3>
<p>
<a href="#back">back</a> (<a href="#back">bk</a>) <a href=
"#breeds-at"><i><breeds></i>-at</a> <a href=
"#breeds-here"><i><breeds></i>-here</a> <a href=
"#breeds-on"><i><breeds></i>-on</a> <a href=
"#can-move">can-move?</a> <a href="#clear-turtles">clear-turtles</a>
(<a href="#clear-turtles">ct</a>) <a href=
"#create-breeds">create-<i><breeds></i></a> <a href=
"#create-ordered-breeds">create-ordered-<i><breeds></i></a>
<a href="#create-ordered-turtles">create-ordered-turtles</a>
(<a href="#cro">cro</a>) <a href="#create-turtles">create-turtles</a>
(<a href="#crt">crt</a>) <a href="#die">die</a> <a href=
"#distance">distance</a> <a href="#distancexy">distancexy</a>
<a href="#downhill">downhill</a> <a href="#downhill4">downhill4</a>
<a href="#dx">dx</a> <a href="#dy">dy</a> <a href="#face">face</a>
<a href="#facexy">facexy</a> <a href="#forward">forward</a> (<a href=
"#forward">fd</a>) <a href="#hatch">hatch</a> <a href=
"#hatch-breeds">hatch-<i><breeds></i></a> <a href=
"#hide-turtle">hide-turtle</a> (<a href="#hide-turtle">ht</a>)
<a href="#home">home</a> <a href="#inspect">inspect</a> <a href=
"#is-breed">is-<i><breed></i>?</a> <a href=
"#is-turtle">is-turtle?</a> <a href="#jump">jump</a> <a href=
"#layout-circle">layout-circle</a> <a href="#left">left</a> (<a href=
"#left">lt</a>) <a href="#move-to">move-to</a> <a href=
"#myself">myself</a> <a href="#nobody">nobody</a> <a href=
"#no-turtles">no-turtles</a> <a href="#of">of</a> <a href=
"#other">other</a> <a href="#patch-ahead">patch-ahead</a> <a href=
"#patch-at">patch-at</a> <a href=
"#patch-at-heading-and-distance">patch-at-heading-and-distance</a>
<a href="#patch-here">patch-here</a> <a href=
"#patch-left-and-ahead">patch-left-and-ahead</a> <a href=
"#patch-right-and-ahead">patch-right-and-ahead</a> <a href=
"#pen-down">pen-down</a> (<a href="#pd">pd</a>) <a href=
"#pen-erase">pen-erase</a> (<a href="#pe">pe</a>) <a href=
"#pen-up">pen-up</a> (<a href="#pu">pu</a>) <a href=
"#random-xcor">random-xcor</a> <a href="#random-ycor">random-ycor</a>
<a href="#right">right</a> (<a href="#rt">rt</a>) <a href=
"#self">self</a> <a href="#set-default-shape">set-default-shape</a>
<a href="#set-line-thickness">__set-line-thickness</a> <a href=
"#setxy">setxy</a> <a href="#shapes">shapes</a> <a href=
"#show-turtle">show-turtle</a> (<a href="#show-turtle">st</a>)
<a href="#sprout">sprout</a> <a href=
"#sprout-breeds">sprout-<i><breeds></i></a> <a href=
"#stamp">stamp</a> <a href="#stamperase">stamp-erase</a> <a href=
"#subject">subject</a> <a href=
"#subtract-headings">subtract-headings</a> <a href="#tie">tie</a>
<a href="#towards">towards</a> <a href="#towardsxy">towardsxy</a>
<a href="#turtle">turtle</a> <a href="#turtle-set">turtle-set</a>
<a href="#turtles">turtles</a> <a href="#turtles-at">turtles-at</a>
<a href="#turtles-here">turtles-here</a> <a href=
"#turtles-on">turtles-on</a> <a href="#turtles-own">turtles-own</a>
<a href="#untie">untie</a> <a href="#uphill">uphill</a> <a href=
"#uphill4">uphill4</a>
<!-- ======================================== -->
<h3>
<a name="patchgroup" id="patchgroup">Patch-related</a>
</h3>
<p>
<a href="#clear-patches">clear-patches</a> (<a href=
"#clear-patches">cp</a>) <a href="#diffuse">diffuse</a> <a href=
"#diffuse4">diffuse4</a> <a href="#distance">distance</a> <a href=
"#distancexy">distancexy</a> <a href=
"#import-pcolors">import-pcolors</a> <a href=
"#import-pcolors-rgb">import-pcolors-rgb</a> <a href=
"#inspect">inspect</a> <a href="#is-patch">is-patch?</a> <a href=
"#myself">myself</a> <a href="#neighbors">neighbors</a> <a href=
"#neighbors4">neighbors4</a> <a href="#nobody">nobody</a> <a href=
"#no-patches">no-patches</a> <a href="#of">of</a> <a href=
"#other">other</a> <a href="#patch">patch</a> <a href=
"#patch-at">patch-at</a> <a href="#patch-ahead">patch-ahead</a>
<a href=
"#patch-at-heading-and-distance">patch-at-heading-and-distance</a>
<a href="#patch-here">patch-here</a> <a href=
"#patch-left-and-ahead">patch-left-and-ahead</a> <a href=
"#patch-right-and-ahead">patch-right-and-ahead</a> <a href=
"#patch-set">patch-set</a> <a href="#patches">patches</a> <a href=
"#patches-own">patches-own</a> <a href=
"#random-pxcor">random-pxcor</a> <a href=
"#random-pycor">random-pycor</a> <a href="#self">self</a> <a href=
"#sprout">sprout</a> <a href=
"#sprout-breeds">sprout-<i><breeds></i></a> <a href=
"#subject">subject</a> <a href="#turtles-here">turtles-here</a>
<!-- ======================================== -->
<h3>
<a name="agentsetgroup" id="agentsetgroup">Agentset</a>
</h3>
<p>
<a href="#all">all?</a> <a href="#any">any?</a> <a href=
"#ask">ask</a> <a href="#ask-concurrent">ask-concurrent</a> <a href=
"#at-points">at-points</a> <a href=
"#breeds-at"><i><breeds></i>-at</a> <a href=
"#breeds-here"><i><breeds></i>-here</a> <a href=
"#breeds-on"><i><breeds></i>-on</a> <a href="#count">count</a>
<a href="#in-cone">in-cone</a> <a href="#in-radius">in-radius</a>
<a href="#is-agent">is-agent?</a> <a href=
"#is-agentset">is-agentset?</a> <a href=
"#is-patch-set">is-patch-set?</a> <a href=
"#is-turtle-set">is-turtle-set?</a> <a href=
"#link-heading">link-heading</a> <a href=
"#link-length">link-length</a> <a href="#link-set">link-set</a>
<a href="#link-shapes">link-shapes</a> <a href=
"#max-n-of">max-n-of</a> <a href="#max-one-of">max-one-of</a>
<a href="#member">member?</a> <a href="#min-n-of">min-n-of</a>
<a href="#min-one-of">min-one-of</a> <a href="#n-of">n-of</a>
<a href="#neighbors">neighbors</a> <a href=
"#neighbors4">neighbors4</a> <a href="#no-patches">no-patches</a>
<a href="#no-turtles">no-turtles</a> <a href="#of">of</a> <a href=
"#one-of">one-of</a> <a href="#other">other</a> <a href=
"#patch-set">patch-set</a> <a href="#patches">patches</a> <a href=
"#sort">sort</a> <a href="#sort-by">sort-by</a> <a href=
"#sort-on">sort-on</a> <a href="#turtle-set">turtle-set</a> <a href=
"#turtles">turtles</a> <a href="#with">with</a> <a href=
"#with-max">with-max</a> <a href="#with-min">with-min</a> <a href=
"#turtles-at">turtles-at</a> <a href="#turtles-here">turtles-here</a>
<a href="#turtles-on">turtles-on</a>
<!-- ======================================== -->
<h3>
<a name="colorgroup" id="colorgroup">Color</a>
</h3>
<p>
<a href="#approximate-hsb">approximate-hsb</a> <a href=
"#approximate-rgb">approximate-rgb</a> <a href=
"#base-colors">base-colors</a> <a href="#color">color</a> <a href=
"#extract-hsb">extract-hsb</a> <a href="#extract-rgb">extract-rgb</a>
<a href="#hsb">hsb</a> <a href="#import-pcolors">import-pcolors</a>
<a href="#import-pcolors-rgb">import-pcolors-rgb</a> <a href=
"#pcolor">pcolor</a> <a href="#rgb">rgb</a> <a href=
"#scale-color">scale-color</a> <a href="#shade-of">shade-of?</a>
<a href="#wrap-color">wrap-color</a>
<!-- ======================================== -->
<h3>
<a name="controlgroup" id="controlgroup">Control flow and logic</a>
</h3>
<p>
<a href="#and">and</a> <a href="#ask">ask</a> <a href=
"#ask-concurrent">ask-concurrent</a> <a href=
"#carefully">carefully</a> <a href="#end">end</a> <a href=
"#error">error</a> <a href="#error-message">error-message</a>
<a href="#every">every</a> <a href="#if">if</a> <a href=
"#ifelse">ifelse</a> <a href="#ifelse-value">ifelse-value</a>
<a href="#let">let</a> <a href="#loop">loop</a> <a href=
"#not">not</a> <a href="#or">or</a> <a href="#repeat">repeat</a>
<a href="#report">report</a> <a href="#run">run</a> <a href=
"#runresult">runresult</a> <a href="#semicolon">; (semicolon)</a>
<a href="#set">set</a> <a href="#stop">stop</a> <a href=
"#startup">startup</a> <a href="#to">to</a> <a href=
"#to-report">to-report</a> <a href="#wait">wait</a> <a href=
"#while">while</a> <a href=
"#with-local-randomness">with-local-randomness</a> <a href=
"#without-interruption">without-interruption</a> <a href=
"#xor">xor</a> <!-- ======================================== -->
<h3>
<a name="taskgroup" id="taskgroup">Task</a>
</h3>
<p>
<a href="#filter">filter</a> <a href="#foreach">foreach</a> <a href=
"#is-command-task">is-command-task?</a> <a href=
"#is-reporter-task">is-reporter-task?</a> <a href="#map">map</a>
<a href="#n-values">n-values</a> <a href="#reduce">reduce</a>
<a href="#run">run</a> <a href="#runresult">runresult</a> <a href=
"#sort-by">sort-by</a> <a href="#task">task</a>
<!-- ======================================== -->
<h3>
<a name="worldgroup" id="worldgroup">World</a>
</h3>
<p>
<a href="#clear-all">clear-all</a> (<a href="#clear-all">ca</a>)
<a href="#clear-drawing">clear-drawing</a> (<a href=
"#clear-drawing">cd</a>) <a href="#clear-patches">clear-patches</a>
(<a href="#clear-patches">cp</a>) <a href=
"#clear-ticks">clear-ticks</a> <a href=
"#clear-turtles">clear-turtles</a> (<a href="#clear-turtles">ct</a>)
<a href="#display">display</a> <a href=
"#import-drawing">import-drawing</a> <a href=
"#import-pcolors">import-pcolors</a> <a href=
"#import-pcolors-rgb">import-pcolors-rgb</a> <a href=
"#no-display">no-display</a> <a href="#max-pxcor">max-pxcor</a>
<a href="#max-pycor">max-pycor</a> <a href="#min-pxcor">min-pxcor</a>
<a href="#min-pycor">min-pycor</a> <a href=
"#patch-size">patch-size</a> <a href="#reset-ticks">reset-ticks</a>
<a href="#resize-world">resize-world</a> <a href=
"#set-patch-size">set-patch-size</a> <a href="#tick">tick</a>
<a href="#tick-advance">tick-advance</a> <a href="#ticks">ticks</a>
<a href="#world-width">world-width</a> <a href=
"#world-height">world-height</a>
<!-- ======================================== -->
<h3>
<a name="perspectivegroup" id="perspectivegroup">Perspective</a>
</h3>
<p>
<a href="#follow">follow</a> <a href="#follow-me">follow-me</a>
<a href="#reset-perspective">reset-perspective</a> (<a href=
"#reset-perspective">rp</a>) <a href="#ride">ride</a> <a href=
"#ride-me">ride-me</a> <a href="#subject">subject</a> <a href=
"#watch">watch</a> <a href="#watch-me">watch-me</a>
<!-- ======================================== -->
<h3>
<a name="hubnetgroup" id="hubnetgroup">HubNet</a>
</h3>
<p>
<a href="#hubnet-broadcast">hubnet-broadcast</a> <a href=
"#hubnet-broadcast-clear-output">hubnet-broadcast-clear-output</a>
<a href="#hubnet-broadcast-message">hubnet-broadcast-message</a>
<a href="#hubnet-clear-override">hubnet-clear-override</a> <a href=
"#hubnet-clear-overrides">hubnet-clear-overrides</a> <a href=
"#hubnet-clients-list">hubnet-clients-list</a> <a href=
"#hubnet-enter-message">hubnet-enter-message?</a> <a href=
"#hubnet-exit-message">hubnet-exit-message?</a> <a href=
"#hubnet-kick-all-clients">hubnet-kick-all-clients</a> <a href=
"#hubnet-kick-client">hubnet-kick-client</a> <a href=
"#hubnet-fetch-message">hubnet-fetch-message</a> <a href=
"#hubnet-message">hubnet-message</a> <a href=
"#hubnet-message-source">hubnet-message-source</a> <a href=
"#hubnet-message-tag">hubnet-message-tag</a> <a href=
"#hubnet-message-waiting">hubnet-message-waiting?</a> <a href=
"#hubnet-reset">hubnet-reset</a> <a href=
"#hubnet-reset-perspective">hubnet-reset-perspective</a> <a href=
"#hubnet-send">hubnet-send</a> <a href=
"#hubnet-send-clear-output">hubnet-send-clear-output</a> <a href=
"#hubnet-send-follow">hubnet-send-follow</a> <a href=
"#hubnet-send-message">hubnet-send-message</a> <a href=
"#hubnet-send-override">hubnet-send-override</a> <a href=
"#hubnet-send-watch">hubnet-send-watch</a> <a href=
"#hubnet-set-client-interface">hubnet-set-client-interface</a>
<!-- ======================================== -->
<h3>
<a name="iogroup" id="iogroup">Input/output</a>
</h3>
<p>
<a href="#beep">beep</a> <a href="#clear-output">clear-output</a>
<a href="#date-and-time">date-and-time</a> <a href=
"#export-view">export-view</a> <a href=
"#export-interface">export-interface</a> <a href=
"#export-output">export-output</a> <a href=
"#export-plot">export-plot</a> <a href=
"#export-all-plots">export-all-plots</a> <a href=
"#export-world">export-world</a> <a href=
"#import-drawing">import-drawing</a> <a href=
"#import-pcolors">import-pcolors</a> <a href=
"#import-pcolors-rgb">import-pcolors-rgb</a> <a href=
"#import-world">import-world</a> <a href=
"#mouse-down">mouse-down?</a> <a href=
"#mouse-inside">mouse-inside?</a> <a href=
"#mouse-xcor">mouse-xcor</a> <a href="#mouse-ycor">mouse-ycor</a>
<a href="#output-print">output-print</a> <a href=
"#output-show">output-show</a> <a href="#output-type">output-type</a>
<a href="#output-write">output-write</a> <a href="#print">print</a>
<a href="#read-from-string">read-from-string</a> <a href=
"#reset-timer">reset-timer</a> <a href=
"#set-current-directory">set-current-directory</a> <a href=
"#show">show</a> <a href="#timer">timer</a> <a href="#type">type</a>
<a href="#user-directory">user-directory</a> <a href=
"#user-file">user-file</a> <a href="#user-new-file">user-new-file</a>
<a href="#user-input">user-input</a> <a href=
"#user-message">user-message</a> <a href=
"#user-one-of">user-one-of</a> <a href=
"#user-yes-or-no">user-yes-or-no?</a> <a href="#write">write</a>
<!-- ======================================== -->
<h3>
<a name="fileiogroup" id="fileiogroup">File</a>
</h3>
<p>
<a href="#file-at-end">file-at-end?</a> <a href=
"#file-close">file-close</a> <a href=
"#file-close-all">file-close-all</a> <a href=
"#file-delete">file-delete</a> <a href=
"#file-exists">file-exists?</a> <a href="#file-flush">file-flush</a>
<a href="#file-open">file-open</a> <a href=
"#file-print">file-print</a> <a href="#file-read">file-read</a>
<a href="#file-read-characters">file-read-characters</a> <a href=
"#file-read-line">file-read-line</a> <a href=
"#file-show">file-show</a> <a href="#file-type">file-type</a>
<a href="#file-write">file-write</a> <a href=
"#user-directory">user-directory</a> <a href=
"#user-file">user-file</a> <a href="#user-new-file">user-new-file</a>
<!-- ======================================== -->
<h3>
<a name="listsgroup" id="listsgroup">List</a>
</h3>
<p>
<a href="#but-first">but-first</a> <a href="#but-last">but-last</a>
<a href="#empty">empty?</a> <a href="#filter">filter</a> <a href=
"#first">first</a> <a href="#foreach">foreach</a> <a href=
"#fput">fput</a> <a href="#histogram">histogram</a> <a href=
"#is-list">is-list?</a> <a href="#item">item</a> <a href=
"#last">last</a> <a href="#length">length</a> <a href=
"#list">list</a> <a href="#lput">lput</a> <a href="#map">map</a>
<a href="#member">member?</a> <a href="#modes">modes</a> <a href=
"#n-of">n-of</a> <a href="#n-values">n-values</a> <a href=
"#of">of</a> <a href="#position">position</a> <a href=
"#one-of">one-of</a> <a href="#reduce">reduce</a> <a href=
"#remove">remove</a> <a href=
"#remove-duplicates">remove-duplicates</a> <a href=
"#remove-item">remove-item</a> <a href=
"#replace-item">replace-item</a> <a href="#reverse">reverse</a>
<a href="#sentence">sentence</a> <a href="#shuffle">shuffle</a>
<a href="#sort">sort</a> <a href="#sort-by">sort-by</a> <a href=
"#sort-on">sort-on</a> <a href="#sublist">sublist</a>
<!-- ======================================== -->
<h3>
<a name="stringgroup" id="stringgroup">String</a>
</h3>
<p>
<a href="#Symbols">Operators (<, >, =, !=, <=, >=)</a>
<a href="#but-first">but-first</a> <a href="#but-last">but-last</a>
<a href="#empty">empty?</a> <a href="#first">first</a> <a href=
"#is-string">is-string?</a> <a href="#item">item</a> <a href=
"#last">last</a> <a href="#length">length</a> <a href=
"#member">member?</a> <a href="#position">position</a> <a href=
"#remove">remove</a> <a href="#remove-item">remove-item</a> <a href=
"#read-from-string">read-from-string</a> <a href=
"#replace-item">replace-item</a> <a href="#reverse">reverse</a>
<a href="#substring">substring</a> <a href="#word">word</a>
<!-- ======================================== -->
<h3>
<a name="mathematicalgroup" id="mathematicalgroup">Mathematical</a>
</h3>
<p>
<a href="#Symbols">Arithmetic Operators (+, *, -, /, ^, <, >,
=, !=, <=, >=)</a> <a href="#abs">abs</a> <a href=
"#acos">acos</a> <a href="#asin">asin</a> <a href="#atan">atan</a>
<a href="#ceiling">ceiling</a> <a href="#cos">cos</a> <a href=
"#num-e">e</a> <a href="#exp">exp</a> <a href="#floor">floor</a>
<a href="#int">int</a> <a href="#is-number">is-number?</a> <a href=
"#ln">ln</a> <a href="#log">log</a> <a href="#max">max</a> <a href=
"#mean">mean</a> <a href="#median">median</a> <a href="#min">min</a>
<a href="#mod">mod</a> <a href="#modes">modes</a> <a href=
"#new-seed">new-seed</a> <a href="#pi">pi</a> <a href=
"#precision">precision</a> <a href="#random">random</a> <a href=
"#random-exponential">random-exponential</a> <a href=
"#random-float">random-float</a> <a href=
"#random-gamma">random-gamma</a> <a href=
"#random-normal">random-normal</a> <a href=
"#random-poisson">random-poisson</a> <a href=
"#random-seed">random-seed</a> <a href="#remainder">remainder</a>
<a href="#round">round</a> <a href="#sin">sin</a> <a href=
"#sqrt">sqrt</a> <a href="#standard-deviation">standard-deviation</a>
<a href="#subtract-headings">subtract-headings</a> <a href=
"#sum">sum</a> <a href="#tan">tan</a> <a href=
"#variance">variance</a>
<!-- ======================================== -->
<h3>
<a name="plottinggroup" id="plottinggroup">Plotting</a>
</h3>
<p>
<a href="#autoplot">autoplot?</a> <a href=
"#auto-plot-off">auto-plot-off</a> <a href=
"#auto-plot-on">auto-plot-on</a> <a href=
"#clear-all-plots">clear-all-plots</a> <a href=
"#clear-plot">clear-plot</a> <a href=
"#create-temporary-plot-pen">create-temporary-plot-pen</a> <a href=
"#export-plot">export-plot</a> <a href=
"#export-all-plots">export-all-plots</a> <a href=
"#histogram">histogram</a> <a href="#plot">plot</a> <a href=
"#plot-name">plot-name</a> <a href=
"#plot-pen-exists">plot-pen-exists?</a> <a href=
"#plot-pen-down">plot-pen-down</a> <a href=
"#plot-pen-reset">plot-pen-reset</a> <a href=
"#plot-pen-up">plot-pen-up</a> <a href="#plot-x-max">plot-x-max</a>
<a href="#plot-x-min">plot-x-min</a> <a href=
"#plot-y-max">plot-y-max</a> <a href="#plot-y-min">plot-y-min</a>
<a href="#plotxy">plotxy</a> <a href=
"#set-current-plot">set-current-plot</a> <a href=
"#set-current-plot-pen">set-current-plot-pen</a> <a href=
"#set-histogram-num-bars">set-histogram-num-bars</a> <a href=
"#set-plot-pen-color">set-plot-pen-color</a> <a href=
"#set-plot-pen-interval">set-plot-pen-interval</a> <a href=
"#set-plot-pen-mode">set-plot-pen-mode</a> <a href=
"#set-plot-x-range">set-plot-x-range</a> <a href=
"#set-plot-y-range">set-plot-y-range</a> <a href=
"#setup-plots">setup-plots</a> <a href=
"#update-plots">update-plots</a>
<!-- ======================================== -->
<h3>
<a name="linkgroup" id="linkgroup">Links</a>
</h3>
<p>
<a href="#both-ends">both-ends</a> <a href=
"#clear-links">clear-links</a> <a href=
"#create-breed-from">create-<breed>-from</a> <a href=
"#create-breed-from">create-<breeds>-from</a> <a href=
"#create-breed-to">create-<breed>-to</a> <a href=
"#create-breed-to">create-<breeds>-to</a> <a href=
"#create-breed-with">create-<breed>-with</a> <a href=
"#create-breeds-with">create-<breeds>-with</a> <a href=
"#create-link-from">create-link-from</a> <a href=
"#create-links-from">create-links-from</a> <a href=
"#create-link-to">create-link-to</a> <a href=
"#create-links-to">create-links-to</a> <a href=
"#create-link-with">create-link-with</a> <a href=
"#create-links-with">create-links-with</a> <a href="#die">die</a>
<a href="#hide-link">hide-link</a> <a href=
"#in-breed-neighbor">in-<breed>-neighbor?</a> <a href=
"#in-breed-neighbors">in-<breed>-neighbors</a> <a href=
"#in-breed-from">in-<breed>-from</a> <a href=
"#in-link-neighbor">in-link-neighbor?</a> <a href=
"#in-link-neighbors">in-link-neighbors</a> <a href=
"#in-link-from">in-link-from</a> <a href=
"#is-directed-link">is-directed-link?</a> <a href=
"#is-link">is-link?</a> <a href="#is-link-set">is-link-set?</a>
<a href="#is-undirected-link">is-undirected-link?</a> <a href=
"#layout-radial">layout-radial</a> <a href=
"#layout-spring">layout-spring</a> <a href=
"#layout-tutte">layout-tutte</a> <a href=
"#breed-neighbor"><breed>-neighbor?</a> <a href=
"#breed-neighbors"><breed>-neighbors</a> <a href=
"#breed-with"><breed>-with</a> <a href=
"#link-heading">link-heading</a> <a href=
"#link-length">link-length</a> <a href=
"#link-neighbor">link-neighbor?</a> <a href="#link">link</a> <a href=
"#links">links</a> <a href="#links-own">links-own</a> <a href=
"#link-breeds-own"><link-breeds>-own</a> <a href=
"#link-neighbors">link-neighbors</a> <a href=
"#link-with">link-with</a> <a href="#my-breeds">my-<breeds></a>
<a href="#my-in-breeds">my-in-<breeds></a> <a href=
"#my-in-links">my-in-links</a> <a href="#my-links">my-links</a>
<a href="#my-out-breeds">my-out-<breeds></a> <a href=
"#my-out-links">my-out-links</a> <a href="#no-links">no-links</a>
<a href="#other-end">other-end</a> <a href=
"#out-breed-neighbor">out-<breed>-neighbor?</a> <a href=
"#out-breed-neighbors">out-<breed>-neighbors</a> <a href=
"#out-breed-to">out-<breed>-to</a> <a href=
"#out-link-neighbor">out-link-neighbor?</a> <a href=
"#out-link-neighbors">out-link-neighbors</a> <a href=
"#out-link-to">out-link-to</a> <a href="#show-link">show-link</a>
<a href="#tie">tie</a> <a href="#untie">untie</a>
<!-- ======================================== -->
<h3>
<a name="moviegroup" id="moviegroup">Movie</a>
</h3>
<p>
<a href="#movie-cancel">movie-cancel</a> <a href=
"#movie-close">movie-close</a> <a href=
"#movie-grab-view">movie-grab-view</a> <a href=
"#movie-grab-interface">movie-grab-interface</a> <a href=
"#movie-set-frame-rate">movie-set-frame-rate</a> <a href=
"#movie-start">movie-start</a> <a href=
"#movie-status">movie-status</a>
<!-- ======================================== -->
<h3>
<a name="behaviorspacegroup" id=
"behaviorspacegroup">BehaviorSpace</a>
</h3>
<p>
<a href="#behaviorspace-run-number">behaviorspace-run-number</a>
<!-- ======================================== -->
<h3>
<a name="systemgroup" id="systemgroup">System</a>
</h3>
<p>
<a href="#netlogo-applet">netlogo-applet?</a> <a href=
"#netlogo-version">netlogo-version</a>
<!-- ======================================== -->
<!-- ======================================== -->
<!-- ======================================== -->
<h2>
<a name="builtinvariables" id="builtinvariables">Built-In
Variables</a>
</h2><!-- ======================================== -->
<h3>
<a name="turtle-variables" id="turtle-variables">Turtles</a>
</h3>
<p>
<a href="#breedvar">breed</a> <a href="#color">color</a> <a href=
"#heading">heading</a> <a href="#hidden">hidden?</a> <a href=
"#label">label</a> <a href="#label-color">label-color</a> <a href=
"#pen-mode">pen-mode</a> <a href="#pen-size">pen-size</a> <a href=
"#shape">shape</a> <a href="#size">size</a> <a href="#who">who</a>
<a href="#xcor">xcor</a> <a href="#ycor">ycor</a>
<!-- ======================================== -->
<h3>
<a name="patch-variables" id="patch-variables">Patches</a>
</h3>
<p>
<a href="#pcolor">pcolor</a> <a href="#plabel">plabel</a> <a href=
"#plabel-color">plabel-color</a> <a href="#pxcor">pxcor</a> <a href=
"#pycor">pycor</a> <!-- ======================================== -->
<h3>
<a name="link-variables" id="link-variables">Links</a>
</h3>
<p>
<a href="#breed">breed</a> <a href="#color">color</a> <a href=
"#end1">end1</a> <a href="#end2">end2</a> <a href=
"#hidden">hidden?</a> <a href="#label">label</a> <a href=
"#label-color">label-color</a> <a href="#shape">shape</a> <a href=
"#thickness">thickness</a> <a href="#tie-mode">tie-mode</a>
<!-- ======================================== -->
<h3>
<a name="other-variables" id="other-variables">Other</a>
</h3>
<p>
<a href="#ques">?</a>
<!-- ======================================== -->
<!-- ======================================== -->
<!-- ======================================== -->
<h2>
<a name="Keywords" id="Keywords">Keywords</a>
</h2>
<p>
<a href="#breed">breed</a> <a href=
"#directed-link-breed">directed-link-breed</a> <a href="#end">end</a>
<a href="#extensions">extensions</a> <a href="#globals">globals</a>
<a href="#includes">__includes</a> <a href="#links-own">links-own</a>
<a href="#patches-own">patches-own</a> <a href="#to">to</a> <a href=
"#to-report">to-report</a> <a href="#turtles-own">turtles-own</a>
<a href="#undirected-link-breed">undirected-link-breed</a>
<!-- ======================================== -->
<!-- ======================================== -->
<!-- ======================================== -->
<h2>
<a name="Constants" id="Constants">Constants</a>
</h2><!-- ======================================== -->
<div class="dict_entry">
<h3>
Mathematical Constants
</h3>
<p>
<b><a name="num-e" id="num-e">e</a></b> = 2.718281828459045
<br>
<b><a name="pi" id="pi">pi</a></b> = 3.141592653589793
</div><!-- ======================================== -->
<div class="dict_entry">
<h3>
<a name="boolconstants" id="boolconstants">Boolean Constants</a>
</h3>
<p>
<b><a name="false" id="false">false</a></b>
<br>
<b><a name="true" id="true">true</a></b>
</div><!-- ======================================== -->
<div class="dict_entry">
<h3>
<a name="color-constants" id="color-constants">Color Constants</a>
</h3>
<p>
<b><a name="colorblack" id="colorblack">black</a></b> = 0
<br>
<b><a name="colorgray" id="colorgray">gray</a></b> = 5
<br>
<b><a name="colorwhite" id="colorwhite">white</a></b> = 9.9
<br>
<b><a name="colorred" id="colorred">red</a></b> = 15
<br>
<b><a name="colororange" id="colororange">orange</a></b> = 25
<br>
<b><a name="colorbrown" id="colorbrown">brown</a></b> = 35
<br>
<b><a name="coloryellow" id="coloryellow">yellow</a></b> = 45
<br>
<b><a name="colorgreen" id="colorgreen">green</a></b> = 55
<br>
<b><a name="colorlime" id="colorlime">lime</a></b> = 65
<br>
<b><a name="colorturquoise" id="colorturquoise">turquoise</a></b> =
75
<br>
<b><a name="colorcyan" id="colorcyan">cyan</a></b> = 85
<br>
<b><a name="colorsky" id="colorsky">sky</a></b> = 95
<br>
<b><a name="colorblue" id="colorblue">blue</a></b> = 105
<br>
<b><a name="colorviolet" id="colorviolet">violet</a></b> = 115
<br>
<b><a name="colormagenta" id="colormagenta">magenta</a></b> = 125
<br>
<b><a name="colorpink" id="colorpink">pink</a></b> = 135
<p>
See the <a href="programming.html#colors">Colors</a> section of the
Programming Guide for more details.
</div><!-- ======================================== -->
<!-- ======================================== -->
<!-- ======================================== -->
<!-- ======================================== -->
<h2>
<a name="A" id="A">A </a>
</h2><!-- ======================================== -->
<div class="dict_entry">
<h3>
<a class="prim" name="abs" id="abs">abs</a>
</h3>
<h4>
abs <i>number</i>
</h4>
<p>
Reports the absolute value of <i>number</i>.
<pre>
show abs -7
=> 7
show abs 5
=> 5
</pre>
</div>
<div class="dict_entry">
<h3>
<a name="acos" id="acos">acos</a>
</h3>
<h4>
acos <i>number</i>
</h4>
<p>
Reports the arc cosine (inverse cosine) of the given number. The
input must be in the range -1 to 1. The result is in degrees, and
lies in the range 0 to 180.
</div>
<div class="dict_entry">
<h3>
<a name="all" id="all">all?</a>
</h3>
<h4>
all? <i>agentset</i> [<i>reporter</i>]
</h4>
<p>
Reports true if all of the agents in the agentset report true for
the given reporter. Otherwise reports false as soon as a
counterexample is found.
<p>
If the agentset is empty, reports true.
<p>
The reporter must report a boolean value for every agent (either
true or false), otherwise an error occurs.
<pre>
if all? turtles [color = red]
[ show "every turtle is red!" ]
</pre>
<p>
See also <a href="#any">any?</a>.
</div>
<div class="dict_entry">
<h3>
<a name="and" id="and">and</a>
</h3>
<h4>
<i>condition1</i> and <i>condition2</i>
</h4>
<p>
Reports true if both <i>condition1</i> and <i>condition2</i> are
true.
<p>
Note that if <i>condition1</i> is false, then <i>condition2</i>
will not be run (since it can't affect the result).
<pre>
if (pxcor > 0) and (pycor > 0)
[ set pcolor blue ] ;; the upper-right quadrant of
;; patches turn blue
</pre>
</div>
<div class="dict_entry">
<h3>
<a name="any" id="any">any?</a>
</h3>
<h4>
any? <i>agentset</i>
</h4>
<p>
Reports true if the given agentset is non-empty, false otherwise.
<p>
Equivalent to "count <i>agentset</i> > 0", but more
efficient (and arguably more readable).
<pre>
if any? turtles with [color = red]
[ show "at least one turtle is red!" ]
</pre>
<p>
Note: nobody is not an agentset. You only get nobody back in
situations where you were expecting a single agent, not a whole
agentset. If any? gets nobody as input, an error results.
<p>
See also <a href="#all">all?</a>, <a href="#nobody">nobody</a>.
</div>
<div class="dict_entry">
<h3>
<a name="approximate-hsb" id="approximate-hsb">approximate-hsb</a>
</h3>
<h4>
approximate-hsb <i>hue saturation brightness</i>
</h4>
<p>
Reports a number in the range 0 to 140, not including 140 itself,
that represents the given color, specified in the HSB spectrum, in
NetLogo's color space.
<p>
All three values should be in the range 0 to 255.
<p>
The color reported may be only an approximation, since the NetLogo
color space does not include all possible colors. (It contains only
certain discrete hues, and for each hue, either saturation or
brightness may vary, but not both -- at least one of the two is
always 255.)
<pre>
show approximate-hsb 0 0 0
=> 0 ;; (black)
show approximate-hsb 127.5 255 255
=> 85.2 ;; (cyan)
</pre>
<p>
See also <a href="#extract-hsb">extract-hsb</a>, <a href=
"#approximate-rgb">approximate-rgb</a>, <a href=
"#extract-rgb">extract-rgb</a>.
</div>
<div class="dict_entry">
<h3>
<a name="approximate-rgb" id="approximate-rgb">approximate-rgb</a>
</h3>
<h4>
approximate-rgb <i>red green blue</i>
</h4>
<p>
Reports a number in the range 0 to 140, not including 140 itself,
that represents the given color, specified in the RGB spectrum, in
NetLogo's color space.
<p>
All three inputs should be in the range 0 to 255.
<p>
The color reported may be only an approximation, since the NetLogo
color space does not include all possible colors. (See <a href=
"#approximate-hsb">approximate-hsb</a> for a description of what
parts of the HSB color space NetLogo colors cover; this is
difficult to characterize in RGB terms.)
<pre>
show approximate-rgb 0 0 0
=> 0 ;; black
show approximate-rgb 0 255 255
=> 85.2 ;; cyan
</pre>
<p>
See also <a href="#extract-rgb">extract-rgb</a>, <a href=
"#approximate-hsb">approximate-hsb</a>, and <a href=
"#extract-hsb">extract-hsb</a>.
</div>
<div class="dict_entry">
<h3>
<a name="Symbols" id="Symbols">Arithmetic Operators</a> (<a name=
"symbolplus" id="symbolplus">+</a>, <a name="symboltimes" id=
"symboltimes">*</a>, <a name="symbolminus" id="symbolminus">-</a>,
<a name="symboldiv" id="symboldiv">/</a>, <a name="symbolexp" id=
"symbolexp">^</a>, <a name="symbollt" id="symbollt"><</a>,
<a name="symbolgt" id="symbolgt">></a>, <a name="symbolequal"
id="symbolequal">=</a>, <a name="symbolnotequal" id=
"symbolnotequal">!=</a>, <a name="symbolltequal" id=
"symbolltequal"><=</a>, <a name="symbolgtequal" id=
"symbolgtequal">>=</a>)
</h3>
<p>
All of these operators take two inputs, and all act as "infix
operators" (going between the two inputs, as in standard
mathematical use). NetLogo correctly supports order of operations
for infix operators.
<p>
The operators work as follows: + is addition, * is multiplication,
- is subtraction, / is division, ^ is exponentiation, < is less
than, > is greater than, = is equal to, != is not equal to,
<= is less than or equal, >= is greater than or equal.
<p>
Note that the subtraction operator (-) always takes two inputs
unless you put parentheses around it, in which case it can take one
input. For example, to take the negative of x, write (- x), with
the parentheses.
<p>
All of the comparison operators also work on strings.
<p>
All of the comparison operators work on agents. Turtles are
compared by who number. Patches are compared top to bottom left to
right, so patch 0 10 is less than patch 0 9 and patch 9 0 is less
than patch 10 0. Links are ordered by end points and in case of a
tie by breed. So link 0 9 is before link 1 10 as the end1 is
smaller, and link 0 8 is less than link 0 9. If there are multiple
breeds of links unbreeded links will come before breeded links of
the same end points and breeded links will be sorted in the order
they are declared in the Code tab.
<p>
Agentsets can be tested for equality or inequality. Two agentsets
are equal if they are the same type (turtle or patch) and contain
the same agents.
<p>
If you are not sure how NetLogo will interpret your code, you
should add parentheses.
<pre>
show 5 * 6 + 6 / 3
=> 32
show 5 * (6 + 6) / 3
=> 20
</pre>
</div>
<div class="dict_entry">
<h3>
<a name="asin" id="asin">asin</a>
</h3>
<h4>
asin <i>number</i>
</h4>
<p>
Reports the arc sine (inverse sine) of the given number. The input
must be in the range -1 to 1. The result is in degrees, and lies in
the range -90 to 90.
</div>
<div class="dict_entry">
<h3>
<a name="ask" id="ask">ask</a>
</h3>
<h4>
ask <i>agentset</i> [<i>commands</i>]
<br>
ask <i>agent</i> [<i>commands</i>]
</h4>
<p>
The specified agent or agentset runs the given commands.
<pre>
ask turtles [ fd 1 ]
;; all turtles move forward one step
ask patches [ set pcolor red ]
;; all patches turn red
ask turtle 4 [ rt 90 ]
;; only the turtle with id 4 turns right
</pre>
<p>
Note: only the observer can ask all turtles or all patches. This
prevents you from inadvertently having all turtles ask all turtles
or all patches ask all patches, which is a common mistake to make
if you're not careful about which agents will run the code you
are writing.
<p>
Note: Only the agents that are in the agentset <i>at the time the
ask begins</i> run the commands.
</div>
<div class="dict_entry">
<h3>
<a name="ask-concurrent" id="ask-concurrent">ask-concurrent</a>
</h3>
<h4>
ask-concurrent <i>agentset</i> [<i>commands</i>]
</h4>
<p>
The agents in the given agentset run the given commands, using a
turn-taking mechanism to produce simulated concurrency. See the
<a href="programming.html#ask-concurrent">Ask-Concurrent</a>
section of the Programming Guide for details on how this works.
<p>
Note: Only the agents that are in the agentset <i>at the time the
ask begins</i> run the commands.
<p>
See also <a href="#without-interruption">without-interruption</a>.
</div>
<div class="dict_entry">
<h3>
<a name="at-points" id="at-points">at-points</a>
</h3>
<h4>
<i>agentset</i> at-points [[<i>x1 y1</i>] [<i>x2 y2</i>] ...]
</h4>
<p>
Reports a subset of the given agentset that includes only the
agents on the patches the given distances away from this agent. The
distances are specified as a list of two-item lists, where the two
items are the x and y offsets.
<p>
If the caller is the observer, then the points are measured
relative to the origin, in other words, the points are taken as
absolute patch coordinates.
<p>
If the caller is a turtle, the points are measured relative to the
turtle's exact location, and not from the center of the patch
under the turtle.
<pre>
ask turtles at-points [[2 4] [1 2] [10 15]]
[ fd 1 ] ;; only the turtles on the patches at the
;; distances (2,4), (1,2) and (10,15),
;; relative to the caller, move
</pre>
</div>
<div class="dict_entry">
<h3>
<a name="atan" id="atan">atan</a>
</h3>
<h4>
atan <i>x y</i>
</h4>
<p>
Converts x and y offsets to a turtle heading in degrees (from 0 to
360).
<p>
Note that this version of atan is designed to conform to the
geometry of the NetLogo world, where a heading of 0 is straight up,
90 is to the right, and so on clockwise around the circle.
(Normally in geometry an angle of 0 is right, 90 is up, and so on,
counterclockwise around the circle, and atan would be defined
accordingly.)
<p>
When y is 0: if x is positive, it reports 90; if x is negative, it
reports 270; if x is zero, you get an error.
<pre>
show atan 1 -1
=> 135
show atan -1 1
=> 315
crt 1 [ set heading 30 fd 1 print atan xcor ycor ]
=> 30
</pre>
<p>
In the final example, note that the result of <tt>atan</tt> equals
the turtle's heading.
<p>
If you ever need to convert a turtle heading (obtained with atan
or otherwise) to a normal mathematical angle, the following should
be helpful:
<pre>
to-report heading-to-angle [ h ]
report (90 - h) mod 360
end
</pre>
</div>
<div class="dict_entry">