# marks

##### Marks of a Point Pattern

Extract or change the marks attached to a point pattern dataset.

##### Usage

`marks(x, …)`# S3 method for ppp
marks(x, …, dfok=TRUE, drop=TRUE)

# S3 method for ppx
marks(x, …, drop=TRUE)

marks(x, …) <- value

# S3 method for ppp
marks(x, …, dfok=TRUE, drop=TRUE) <- value

# S3 method for ppx
marks(x, …) <- value

setmarks(x, value)

x %mark% value

##### Arguments

- x
Point pattern dataset (object of class

`"ppp"`

or`"ppx"`

).- …
Ignored.

- dfok
Logical. If

`FALSE`

, data frames of marks are not permitted and will generate an error.- drop
Logical. If

`TRUE`

, a data frame consisting of a single column of marks will be converted to a vector or factor.- value
Replacement value. A vector, data frame or hyperframe of mark values, or

`NULL`

.

##### Details

These functions extract or change the marks
attached to the points of the point pattern `x`

.

The expression `marks(x)`

extracts the marks of `x`

.
The assignment `marks(x) <- value`

assigns new marks to the
dataset `x`

, and updates the dataset `x`

in the current
environment. The expression `setmarks(x,value)`

or equivalently `x %mark% value`

returns a point pattern
obtained by replacing the marks of `x`

by `value`

, but does
not change the dataset `x`

itself.

For point patterns in two-dimensional space (objects of class
`"ppp"`

) the marks can be a vector, a factor, or a data frame.

For general point patterns (objects of class "ppx") the marks can be a vector, a factor, a data frame or a hyperframe.

For the assignment `marks(x) <- value`

, the `value`

should be a vector or factor of length equal to the number of
points in `x`

, or a data frame or hyperframe with as many rows
as there are points in `x`

. If `value`

is a single value,
or a data frame or hyperframe with one row, then it will be replicated
so that the same marks will be attached to each point.

To remove marks, use `marks(x) <- NULL`

or
`unmark(x)`

.

Use `ppp`

or `ppx`

to create point patterns in more general
situations.

##### Value

For `marks(x)`

, the result is a vector, factor, data frame or hyperframe,
containing the mark values attached to the points of `x`

.

For `marks(x) <- value`

, the result is the updated point pattern
`x`

(with the side-effect that the dataset `x`

is updated in
the current environment).

For `setmarks(x,value)`

and `x %mark% value`

, the return value
is the point pattern obtained by replacing the
marks of `x`

by `value`

.

##### See Also

##### Examples

```
# NOT RUN {
X <- amacrine
# extract marks
m <- marks(X)
# recode the mark values "off", "on" as 0, 1
marks(X) <- as.integer(m == "on")
# }
```

*Documentation reproduced from package spatstat, version 1.55-1, License: GPL (>= 2)*