Convex Hull - Revision history

Fei: /* ConvexHull.lse */

2006-11-08T23:22:40Z

ConvexHull.lse

← Older revision		Revision as of 23:22, 8 November 2006
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	ENDPI		ENDPI
	TRANSITIONS		TRANSITIONS
	// Continue until we reach the ending pivot location (which is actually second time we hit the second pivot vertex,		// Continue until we reach the ending pivot location (which is actually second time we hit the second pivot vertex,
	// since the first pivot vertex gets only partially processed on first pass)		// since the first pivot vertex gets only partially processed on first pass)
	TRANSITIONS = (PivotLocation NEQ EndingPivotLoc)		TRANSITIONS = (PivotLocation NEQ EndingPivotLoc)

Fei: /* Suggested Experiments */

2006-11-08T20:58:22Z

Suggested Experiments

← Older revision		Revision as of 20:58, 8 November 2006
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	To explore this cellular automata model further, try the following:		To explore this cellular automata model further, try the following:
	~~#Vary pInitial and see what affect this has.~~
	~~#Change OVER REGION CENTRED to another value. Try "2". What happes when neighbours can live further away from origin cells?~~
	~~#Change 'numNeighbs EQ 3' to 'numNeighbs EQ 2'; what happens?~~
	~~#Example: changed pInitial to 0.005 and in GameOfLife.lse "CellState = IF (CellState EQ 0) AND (numNeighbs EQ 2) THEN 1"...~~
	~~[[Image:GameOfLife_Gliders.jpg]]~~

	~~The left window is zoomed (use right mouse button) so you can see a close-up of several groups of cells that move across this virtual landscape.~~

Fei: /* GameOfLife.lse */

2006-11-08T20:57:46Z

GameOfLife.lse

← Older revision		Revision as of 20:57, 8 November 2006
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	Output Frequency: 1		Output Frequency: 1

	===~~GameOfLife~~.lse===		===ConvexHull.lse===

	// Sweep-line approach to identifying convex hull using a worker agent		// Sweep-line approach to identifying convex hull using a worker agent
	LSAGENT: ConvexHull		LSAGENT: ConvexHull

	DEFINITIONS		DEFINITIONS
	LAYER: StudyArea, ConvexHull, ConvexHullPoints		LAYER: StudyArea, ConvexHull, ConvexHullPoints

	GLOBAL VARIABLE: TRLoc		GLOBAL VARIABLE: TRLoc
	LOCAL VARIABLE: EndingPivotLoc		LOCAL VARIABLE: EndingPivotLoc

	AGENT VARIABLE: PivotLocation, EdgeLocation, EdgeRow, EdgeCol		AGENT VARIABLE: PivotLocation, EdgeLocation, EdgeRow, EdgeCol
	ENDDEF		ENDDEF

	INITIALSTATE		INITIALSTATE
	INITIALSTATE = 1		INITIALSTATE = 1
			// Find the top-right-most point
	// Find the top-right-most point
	TRLoc = 0		TRLoc = 0
	OVER REGION WHOLE MAP		OVER REGION WHOLE MAP
Line 62:		Line 57:
	TRLoc = MAX(TRLoc, Location)		TRLoc = MAX(TRLoc, Location)
	ENDFN		ENDFN
			ConvexHull = 1 // Initialize convex hull layer to all ones (will erase areas outside hull)
	ConvexHull = 1 // Initialize convex hull layer to all ones (will erase areas outside hull)
	ENDIS		ENDIS

	NUMAGENTS = 1 // Only need a single worker		NUMAGENTS = 1 // Only need a single worker

	// Start on the first pivot vertex on convex hull		// Start on the first pivot vertex on convex hull
	AGENTLOCATION		AGENTLOCATION
	REGION LOCATION(TRLoc)		REGION LOCATION(TRLoc)
	ENDAL		ENDAL

	PROBINIT		PROBINIT
	PROBINIT = 1		PROBINIT = 1
			// Set up first pivot vertex, and first raster boundary location
	// Set up first pivot vertex, and first raster boundary location
	PivotLocation = Location		PivotLocation = Location
	EdgeRow = NUMROWS-1		EdgeRow = NUMROWS-1
Line 83:		Line 73:
	EndingPivotLoc = -1		EndingPivotLoc = -1
	ENDPI		ENDPI

	TRANSITIONS		TRANSITIONS
	// Continue until we reach the ending pivot location (which is actually second time we hit the second pivot vertex,		// Continue until we reach the ending pivot location (which is actually second time we hit the second pivot vertex,
	// since the first pivot vertex gets only partially processed on first pass)		// since the first pivot vertex gets only partially processed on first pass)
	TRANSITIONS = (PivotLocation NEQ EndingPivotLoc)		TRANSITIONS = (PivotLocation NEQ EndingPivotLoc)
			ConvexHullPoints = 1
	ConvexHullPoints = 1		// Walk line from boundary to vertex and erase until a new pivot vertex is hit (then move there)

	// Walk line from boundary to vertex and erase until a new pivot vertex is hit (then move there)
	oldPivot = PivotLocation		oldPivot = PivotLocation
	hitPivot = FALSE		hitPivot = FALSE
	OVER REGION VECTOR(EdgeLocation, PivotLocation)		OVER REGION VECTOR(EdgeLocation, PivotLocation)
	DECISION !hitPivot		DECISION !hitPivot
			IF (StudyArea > 0) // hit new vertex
	IF (StudyArea > 0) // hit new vertex
	hitPivot = TRUE		hitPivot = TRUE
	IF (EndingPivotLoc EQ -1) AND (Location NEQ PivotLocation)		IF (EndingPivotLoc EQ -1) AND (Location NEQ PivotLocation)
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	ENDFN		ENDFN
	ENDFN		ENDFN
			// Move boundary location clockwise around outside edge of raster
	// Move boundary location clockwise around outside edge of raster
	IF (EdgeRow EQ NUMROWS-1) AND (EdgeCol < NUMCOLS-1)		IF (EdgeRow EQ NUMROWS-1) AND (EdgeCol < NUMCOLS-1)
	EdgeCol = EdgeCol + 1		EdgeCol = EdgeCol + 1

Fei: /* GameOfLife.lse */

2006-11-08T20:56:00Z

GameOfLife.lse

← Older revision		Revision as of 20:56, 8 November 2006
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	===GameOfLife.lse===		===GameOfLife.lse===

	/* This file contains a ~~landscape event definition for Conway's Game of Life */~~		// Sweep-line approach to identifying convex hull using a worker agent
	~~LSEVENT~~: ~~GameOfLife~~		LSAGENT: ConvexHull

	DEFINITIONS		DEFINITIONS
	LAYER: ~~CellState~~, ~~PrevCellState~~		LAYER: StudyArea, ConvexHull, ConvexHullPoints
	GLOBAL VARIABLE: ~~pInitial~~
			GLOBAL VARIABLE: TRLoc
			LOCAL VARIABLE: EndingPivotLoc

			AGENT VARIABLE: PivotLocation, EdgeLocation, EdgeRow, EdgeCol
	ENDDEF		ENDDEF

	INITIALSTATE		INITIALSTATE
	INITIALSTATE = 1		INITIALSTATE = 1
	~~CellState~~ = ~~IF UNIFORM~~(0,1) ~~< pInitial THEN 1 ELSE 0~~
			// Find the top-right-most point
			TRLoc = 0
			OVER REGION WHOLE MAP
			DECISION StudyArea > 0
			TRLoc = MAX(TRLoc, Location)
			ENDFN

			ConvexHull = 1 // Initialize convex hull layer to all ones (will erase areas outside hull)
	ENDIS		ENDIS
	~~RETURNTIME~~
	~~RETURNTIME~~ = 1		NUMAGENTS = 1 // Only need a single worker
	~~PrevCellState~~ = ~~CellState~~
	~~ENDRT~~		// Start on the first pivot vertex on convex hull
			AGENTLOCATION
			REGION LOCATION(TRLoc)
			ENDAL

			PROBINIT
			PROBINIT = 1

			// Set up first pivot vertex, and first raster boundary location
			PivotLocation = Location
			EdgeRow = NUMROWS-1
			EdgeCol = COL(Location)
			EdgeLocation = LOCATION(EdgeRow, EdgeCol)
			EndingPivotLoc = -1
			ENDPI

	TRANSITIONS		TRANSITIONS
	TRANSITIONS = ~~TRUE~~		// Continue until we reach the ending pivot location (which is actually second time we hit the second pivot vertex,
	~~numNeighbs~~ = 0		// since the first pivot vertex gets only partially processed on first pass)
	OVER REGION ~~CENTRED~~(1,~~1.5, EUCLIDEAN~~)		TRANSITIONS = (PivotLocation NEQ EndingPivotLoc)
	DECISION ~~PrevCellState~~ EQ 1
	~~numNeighbs~~ = ~~numNeighbs + 1~~		ConvexHullPoints = 1
	ENDFN
	~~CellState~~ = IF (~~CellState~~ EQ 0) AND (~~numNeighbs EQ 3~~) ~~THEN~~ 1		// Walk line from boundary to vertex and erase until a new pivot vertex is hit (then move there)
	ELSE IF (~~CellState~~ EQ 1) AND (~~2 <~~= ~~numNeighbs <~~= ~~3) THEN~~ 1		oldPivot = PivotLocation
	ELSE 0		hitPivot = FALSE
			OVER REGION VECTOR(EdgeLocation, PivotLocation)
			DECISION !hitPivot

			IF (StudyArea > 0) // hit new vertex
			hitPivot = TRUE
			IF (EndingPivotLoc EQ -1) AND (Location NEQ PivotLocation)
			EndingPivotLoc = PivotLocation
			ENDFN
			PivotLocation = Location
			ELSE
			ConvexHull = 0 // erase
			ENDFN
			ENDFN

			// Move boundary location clockwise around outside edge of raster
			IF (EdgeRow EQ NUMROWS-1) AND (EdgeCol < NUMCOLS-1)
			EdgeCol = EdgeCol + 1
			ELSE IF (EdgeCol EQ NUMCOLS-1) AND (EdgeRow > 0)
			EdgeRow = EdgeRow - 1
			ELSE IF (EdgeRow EQ 0) AND (EdgeCol > 0)
			EdgeCol = EdgeCol - 1
			ELSE
			EdgeRow = EdgeRow + 1
			ENDFN
			EdgeLocation = LOCATION(EdgeRow, EdgeCol)
	ENDTR		ENDTR
			POPULATIONTIME = 1
	~~Comments: more here...~~		// Move to current/new pivot location
			MOVELOCATION
			REGION LOCATION(PivotLocation)
			ENDML

	==Suggested Experiments==		==Suggested Experiments==

Fei: /* GameOfLife.sel */

2006-11-08T20:53:38Z

GameOfLife.sel

← Older revision		Revision as of 20:53, 8 November 2006
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	//SimStart 100000 1		//SimStart 100000 1

	===~~GameOfLife~~.sel===		===Model.sel===

	Seles Model		Seles Model
	~~Model Size: 200, 200~~		Time Units: Step kiloStep 1000 100000
	Time Units: na Step 1
	Landscape Events:		Landscape Events:
	~~GameOfLife~~.lse		ConvexHull.lse
	~~Variable-Output View Maps~~:		Spatial Constants:
	~~CellState~~		StudyArea
	~~PrevCellState~~		Spatial Variables:
	~~Output Model Bounds~~:		ConvexHullPoints[1] <= 0
	~~CellState:~~ 1		ConvexHull[1] <= 0
	~~PrevCellState:~~ 1
	Global Variables:		Global Variables:
	~~pInitial~~ = 0~~.05~~		TRLoc = 0
	Output Frequency: 1		Output Frequency: 1

	~~Comments: more here...~~

	===GameOfLife.lse===		===GameOfLife.lse===

Fei: /* MLM.scn */

2006-11-08T20:52:34Z

MLM.scn

← Older revision		Revision as of 20:52, 8 November 2006
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	$gisData$ = ..\..\CaseStudy_Morice\gisData\cell		$gisData$ = ..\..\CaseStudy_Morice\gisData\cell
	StudyArea = $gisData$\BEC		StudyArea = $gisData$\BEC

	Model Dimensions: StudyArea		Model Dimensions: StudyArea
	Model.sel		Model.sel
	SimPriority Low Priority		SimPriority Low Priority

	//SimStart 100000 1		//SimStart 100000 1

Fei: /* Convex Hull.scn */

2006-11-08T20:52:07Z

Convex Hull.scn

← Older revision		Revision as of 20:52, 8 November 2006
Line 14:		Line 14:
	In the following sections we will examine all of the model files for this model. Note that instead of downloading the zip file above, you could just copy the text in the boxes below into a text editor and save it with the appropriate name (Section title). Opening the resulting .scn file in the SELES simulator would run this model.		In the following sections we will examine all of the model files for this model. Note that instead of downloading the zip file above, you could just copy the text in the boxes below into a text editor and save it with the appropriate name (Section title). Opening the resulting .scn file in the SELES simulator would run this model.

	===~~Convex Hull~~.scn===		===MLM.scn===

	SELES Scenario		SELES Scenario
	$gisData$ = ..\..\CaseStudy_Morice\gisData\cell		$gisData$ = ..\..\CaseStudy_Morice\gisData\cell
	StudyArea = $gisData$\BEC		StudyArea = $gisData$\BEC

	Model Dimensions: StudyArea		Model Dimensions: StudyArea
	Model.sel		Model.sel
	SimPriority Low Priority		SimPriority Low Priority

	//SimStart 100000 1		//SimStart 100000 1

	===GameOfLife.sel===		===GameOfLife.sel===

Fei: /* GameOfLife.scn */

2006-11-08T20:51:26Z

GameOfLife.scn

← Older revision		Revision as of 20:51, 8 November 2006
Line 14:		Line 14:
	In the following sections we will examine all of the model files for this model. Note that instead of downloading the zip file above, you could just copy the text in the boxes below into a text editor and save it with the appropriate name (Section title). Opening the resulting .scn file in the SELES simulator would run this model.		In the following sections we will examine all of the model files for this model. Note that instead of downloading the zip file above, you could just copy the text in the boxes below into a text editor and save it with the appropriate name (Section title). Opening the resulting .scn file in the SELES simulator would run this model.

	===~~GameOfLife~~.scn===		===Convex Hull.scn===

	Scenario ~~Information // This statement in the~~ .~~scn file begins each and every SELES model~~		SELES Scenario
	~~GameOfLife~~.~~sel // This line tells SELES to go and find the correct~~ .~~sel model file~~		$gisData$ = ..\..\CaseStudy_Morice\gisData\cell
	~~SimPriority Low Priority // This line priorizes the modelling process versus other tasks your computer has going~~.		StudyArea = $gisData$\BEC
	~~// More information on SimPriority can be found in [[Scenario Reference]] under Simulation Control.~~

	~~Comments~~: ~~More..~~.		Model Dimensions: StudyArea
			Model.sel
			SimPriority Low Priority

			//SimStart 100000 1

	===GameOfLife.sel===		===GameOfLife.sel===

Fei: /* GameOfLife.scn */

2006-11-08T20:50:16Z

GameOfLife.scn

← Older revision		Revision as of 20:50, 8 November 2006
Line 42:		Line 42:
	Comments: more here...		Comments: more here...

	===GameOfLife.~~scn~~===		===GameOfLife.lse===

	/* This file contains a landscape event definition for Conway's Game of Life */		/* This file contains a landscape event definition for Conway's Game of Life */

Fei at 20:47, 8 November 2006

2006-11-08T20:47:13Z

← Older revision		Revision as of 20:47, 8 November 2006
Line 1:		Line 1:
	==Summary==		==Summary==

	In the 1970s a two-state, two dimensional cellular automaton named Game of Life became very widely known, particularly among the early computing community. Invented by John Conway, and popularized by Martin Gardner in a Scientific American article, its rules are as follows: If a black cell has 2 or 3 black neighbors, it stays black. If a white cell has 3 black neighbors, it becomes black. In all other cases, the cell becomes white. Despite the simplicity of the rule, an impressive diversity of behavior is achieved, fluctuating between apparent randomness and order. One of the most apparent features of the Game of Life is the frequent occurrence of gliders, which are arrangements of cells that essentially move themselves across the grid.
	~~(from http://en.wikipedia.org/wiki/Cellular_automaton)~~

	==Screenshot==		==Screenshot==

	[[Image:~~GameOfLife~~.~~jpg~~]]		[[Image:ConvexHull.gif]]

	A screenshot of SELES simulator with the two windows of the GameOfLife model. The window on the right shows the initial distribution of live cells. For this example, the probility of initiation (pInitial, see GameOfLife.lse below) was set to 0.05. That is, a random selection of 5% of the cells are given a value of 1 (= "live"). In the left hand window, the NumNeighbs rule in GameOfLife.lse has been fired one time. Since lots of live cells have less than 3 live neighbours, many cells 'die'.

	==Download Model==		==Download Model==

	Download the .scn, .sel and .lse files by clicking on the following link: [[Image:~~GameOfLife.zip\|GameOfLife~~.zip]]		Download the .scn, .sel and .lse files by clicking on the following link: [[Image:ConvexHull.zip]]

	==Model Code Exploration==		==Model Code Exploration==