Move the turtles backward of their headings' directions.

bk(turtles, dist, world, torus = FALSE, out = TRUE)

# S4 method for agentMatrix,numeric
bk(turtles, dist, world, torus = FALSE, out = TRUE)

## Arguments

turtles AgentMatrix object representing the moving agents. Numeric. Vector of distances to move. Must be of length 1 or of length turtles. WorldMatrix or worldArray object. Logical to determine if the world is wrapped. Default is torus = FALSE. Logical. Determine if a turtle should move when torus = FALSE and its ending position will be outside of the world's extent. Default is out = TRUE.

## Value

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

## Details

If torus = FALSE and out = TRUE, world does not need to be provided.

If a distance to move leads a turtle outside of the world's extent and torus = TRUE, the turtle is relocated on the other side of the world, inside its extent; if torus = FALSE and out = TRUE, the turtle moves past the world's extent; if torus = FALSE and out = FALSE, the turtle does not move at all. In the event that a turtle does not move, its previous coordinates are still updated with its position before running bk() (i.e., its current position).

If a given dist value is negative, then the turtle moves forward.

The turtles' headings are not affected by the function (i.e., the turtles do not face backward).

Wilensky, U. 1999. NetLogo. http://ccl.northwestern.edu/netlogo/. Center for Connected Learning and Computer-Based Modeling, Northwestern University. Evanston, IL.

w1 <- createWorld(minPxcor = 0, maxPxcor = 4, minPycor = 0, maxPycor = 4,
points(t1, col = of(agents = t1, var = "color"), pch = 16) 