Move the turtles to their neighboring patch with the highest value.

uphill(world, pVar, turtles, nNeighbors, torus = FALSE)

# S4 method for worldMatrix,missing,agentMatrix,numeric
uphill(world, turtles, nNeighbors, torus)

# S4 method for worldArray,character,agentMatrix,numeric
uphill(world, pVar, turtles, nNeighbors, torus = FALSE)



WorldMatrix or worldArray object.


Character. If the world is a worldArray object, pVar is the name of the layer to use to define the patches values. pVar must not be provided if the world is a worldMatrix object.


AgentMatrix object representing the moving agents.


Integer: 4 or 8. Represents the number of neighbor patches considered.


Logical to determine if the world is wrapped. Default is torus = FALSE.


AgentMatrix representing the turtles with updated coordinates and updated data for their heading values and previous coordinates prevX and prevY.


If no neighboring patch has a larger value than the patch where the turtle is currently located on, the turtle stays on this patch. It still moves to the patch center if it was not already on it.

If there are multiple neighboring patches with the same highest value, the turtle chooses one patch randomly.

If a turtle is located on a patch on the edge of the world and torus = FALSE, it has fewer neighboring patches as options to move than nNeighbors; if torus = TRUE, the turtle can move on the other side of the world to move uphill and its choice of neighboring patches is always equals to nNeighbors.


Wilensky, U. 1999. NetLogo. Center for Connected Learning and Computer-Based Modeling, Northwestern University. Evanston, IL.


Sarah Bauduin


w1 <- createWorld(minPxcor = 1, maxPxcor = 10, minPycor = 1, maxPycor = 10,
                          data = runif(100))
t1 <- createTurtles(n = 10, coords = randomXYcor(w1, n = 10))
points(t1, col = of(agents = t1, var = "color"), pch = 16)

t1 <- uphill(world = w1, turtles = t1, nNeighbors = 8)
points(t1, col = of(agents = t1, var = "color"), pch = 16)