I am working in a program in Netlogo and I want to divide the world in upper-quadrant and lower-quadrant and ask turtles to move to the upper-quadrant. I have figured out how to divide the world in four quadrant from a previous question answered here, but I don't know how to divide it in two.
ask patches with [ pxcor <= max-pxcor and pxcor > 0 and pycor > 0]
[
set pcolor red
set quadrant 1
]
ask patches with [ pxcor >= min-pxcor and pxcor < 0 and pycor > 0]
[
set pcolor blue
set quadrant 2
]
ask patches with [ pxcor <= max-pxcor and pxcor > 0 and pycor < 0]
[
set pcolor green
set quadrant 3
]
ask patches with [ pxcor >= min-pxcor and pxcor < 0 and pycor < 0]
[
set pcolor yellow
set quadrant 4
]
Given that you are interested in a lower and an upper quadrant, you only need to look at y coordinates. The specific condition depends on where your world's origin (i.e. coordinates [0;0]) is.
If your world's origin is in the default position, which is the center, then do:
patches-own [
quadrant
]
to setup
clear-all
ask patches [
ifelse (pycor > 0)
[set quadrant 1]
[set quadrant 2]
]
end
If your world's origin is in a corner (e.g. I assume bottom left corner in this case), just do:
patches-own [
quadrant
]
to setup
clear-all
ask patches [
ifelse (pycor > max-pycor / 2)
[set quadrant 1]
[set quadrant 2]
]
end
If you don't know in advance where your world's origin will be, or if your world's origin is in a less common place than the two examples above, you can take a more generalised approach that fits any situation:
patches-own [
quadrant
]
to setup
clear-all
let y-extent (max-pycor - min-pycor + 1)
ask patches [
ifelse (pycor > y-extent / 2)
[set quadrant 1]
[set quadrant 2]
]
end