Commands Affecting Patchest (Printable)

average-of-patches `[list of commands]` [Observer, Turtle]

Returns the numerical average of the [list of commands] when evaluated accross all the patches.

ca, clearall [Observer]

Kills all turtles, sets all patches to black, and resets all patch variables.

cg, cleargraphics [Observer]

Sets all patches to black

count-patches-with `ilist` [Observer, Turtle]

Returns the number of patches whose `ilist` is true.
Sample usage:
`show count-patches-with [(distance 0 0) < 5]`
This gives the number of patches inside a circle of radius 5 centered at the origin.

count-pc `color` [Observer, Turtle]

Returns the number of patches that are the color `color`.

cp, clearpatches [Observer]

Sets all patches to black and resets all patch variables.

diffuse `variable percentage` [Observer]

Makes each patch give 1/8 of `percentage` of `variable` to each neighboring patch.
Note:percentage should be expressed as a number between 0 and 1.

diffuse4 `variable percentage` [Observer]

Makes each patch give 1/4 of `percentage` of `variable` to each neighboring patch to the N, S, E and W.
Note:percentage should be expressed as a number between 0 and 1.

max-of-patches-with `pred-ilist ilist`

Reports the highest value of `ilist` when run over the turtles that statisfy `pred-ilist`. If there are no patches in which `pred-ilist` is true, reports `minnum`, the smallest number possible without going into negative infinity. Note: This command can also be executed by patches, for example within an `ask-patches` statement.

median-of-patches `[list of commands]` [Observer, Turtle]

Returns the median of the [list of commands] when [list of commands] is evaluated by all patches.

min-of-patches-with `pred-ilist ilist`

Reports the lowest value of `ilist` when run over the turtles that statisfy `pred-ilist`. If there are no patches in which `pred-ilist` is true, reports `maxnum`, the largest number possible without going into positive infinity. Note: This command can also be executed by patches, for example within an `ask-patches` statement.

mode-of-patches `[list of commands]` [Observer, Turtle]

Returns the mode of the given [list of commands] when evaluated accross all the patches.

nsum `variable1 variable2` [Observer]

For each patch, takes the sum of `variable1` from all neighboring patches and places it in `variable2`

nsum4 `variable1 variable2` [Observer]

For each patch, takes the sum of `variable1` from the non-diagonal (N,E,S,W) neighboring patches and places it in `variable2`

pc, patchcolor [Turtle]

Reports the color of the patch the turtle is on.
Please see the color reference for more info on colors.

pc-ahead [Turtle]

Reports the color of the patch one space ahead in the direction that the turtle is facing.
Please see the color reference for more info on colors.

pc-at `xcor ycor` [Observer, Turtle]

Reports the color of the patch `xcor` units in the x direction and `ycor` units in the y direction away from the caller.
Please see the color reference for more info on colors.

pc-towards `angle distance` [Observer, Turtle]

Reports the color of the patch `distance` away at a relative heading of `angle`.
Please see the color reference for more info on colors.

pstamp `color` [Observer]

Allows patches to set the color of the turtle that is on it to `color.`

pstamp-at `xcor ycor color` [Observer]

Allows patches to set the color of the turtle `xcor` patches in the x-direction and `ycor` patches in the y-direction away to `color.`

pstamp-towards `radius angle color` [Observer]

Allows patches to set the color of the turtle `radius` units away at an angle of `angle` to `color.`

scale-pc `color variable limit1 limit2` [Observer]

Patches set their color to a shade of `color` based on their value of `variable`. `limit1` and `limit2` determine the amount of gradation.
Example:
`scale-color green density 0 20`
Patches turn one of twenty shades of green. Patches with lower density turn darker green.
`scale-color blue energy 20 0`
Patches turn one of twenty shades of green. Patches with lower density turn lighter green.
NOTE: This is a patch command. It must be called from within an `ask-patches` or `ask-patch-at` statement

sdev-of-patches `[list of commands]` [Observer, Turtle]

Returns the standard deviation of the given [list of commands] when evaluated accross all the patches.

setpc, setpatchcolor `color` [Observer, Turtle]

This command has two different uses. It can be run as a turtle command, in which case it will set the color of the patches which are underneath turtles to `color`. It can also be run as a patch command, inside either an `ask-patches` or `ask-patch-at` statement. In these cases, the patches being asked will set their color to `color`.

stamp `color` [Observer, Turtle]

Sets color of patch under turtle to `color`

stamp-at `xcor ycor color` [Observer, Turtle]

Sets the color of the patch `xcor` units in the x direction and `ycor` units in the y direction away from the caller to `color`.

stamp-towards `angle distance color` [Turtle]

Sets the color of the patch `distance` away, if the heading were `angle`, to `color`.

sum-of-patches `ilist` [Observer, Turtle]

Reports the total of evaluating `ilist`in every patch and adding it up.
Example usage: `show sum-of-patches [food]`
This gives the total amount of food in the world.

sum-of-patches-with `pred-ilist ilist` [Observer, Turtle]

Reports the total value of `ilist` when run over the turtles that statisfy `pred-ilist`. If there are no patches in which `pred-ilist` is true, reports 0. Note: This command can also be executed by patches, for example within an `ask-patches` statement.
Example: `sum-of-patches-with (pc = green or pc = blue) [density]` returns the sum of the densities of all patches which are blue or green.

variance-of-patches `[list of commands]` [Observer, Turtle]

Returns the variance [list of commands] amongst all the patches.