Spreading1

A simple model to demonstrate spread across a landscape from a single point.

Spreading.lse

LSEVENT: SpreadingTypes

DEFINITIONS

 LAYER: DistanceFromSrc, Visited

 GLOBAL VARIABLE: SpreadType

 CLUSTER VARIABLE: StartLocation
 CELL VARIABLE: distInc, d

ENDDEF

RETURNTIME

  RETURNTIME = 0
  DistanceFromSrc = (NUMROWS^2 + NUMCOLS^2)^0.5

ENDRT

EVENTLOCATION

  REGION LOCATION(LOCATION(NUMROWS/2, NUMCOLS/2))

ENDEL

PROBINIT

 PROBINIT = 1
 StartLocation = Location
 distInc = 0
 d = 0

ENDPI

TRANSITIONS

 TRANSITIONS = (d < DistanceFromSrc)
 Visited = 1
 DistanceFromSrc = d

ENDTR

SPREADTIMESTEP = distInc

SPREADLOCATION

  maxD = IF (1 <= SpreadType <= 3) THEN 1.5 ELSE 1
  
  REGION CENTRED(1, maxD)
     DECISION DistanceFromSrc > (DISTANCE(StartLocation, Location))

ENDSL

SPREADPROB

  SPREADPROB = 1
  d = ROUND(DISTANCE(StartLocation, Location))
  distInc = CLASSIFY(SpreadType)
              0: 1
              1: 1
              2: DISTANCE(Location, SOURCE Location)
              3: MAX(0,d - SOURCE DistanceFromSrc)
             ENDFN

ENDSP

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