# as.lpp

##### Convert Data to a Point Pattern on a Linear Network

Convert various kinds of data to a point pattern on a linear network.

##### Usage

```
as.lpp(x=NULL, y=NULL, seg=NULL, tp=NULL, …,
marks=NULL, L=NULL, check=FALSE, sparse)
```

##### Arguments

- x,y
Vectors of cartesian coordinates, or any data acceptable to

`xy.coords`

. Alternatively`x`

can be a point pattern on a linear network (object of class`"lpp"`

) or a planar point pattern (object of class`"ppp"`

).- seg,tp
Optional local coordinates. Vectors of the same length as

`x,y`

. See Details.- …
Ignored.

- marks
Optional marks for the point pattern. A vector or factor with one entry for each point, or a data frame or hyperframe with one row for each point.

- L
Linear network (object of class

`"linnet"`

) on which the points lie.- check
Logical. Whether to check the validity of the spatial coordinates.

- sparse
Optional logical value indicating whether to store the linear network data in a sparse matrix representation or not. See

`linnet`

.

##### Details

This function converts data in various formats into a point pattern
on a linear network (object of class `"lpp"`

).

The possible formats are:

`x`

is already a point pattern on a linear network (object of class`"lpp"`

). Then`x`

is returned unchanged.`x`

is a planar point pattern (object of class`"ppp"`

). Then`x`

is converted to a point pattern on the linear network`L`

using`lpp`

.`x,y,seg,tp`

are vectors of equal length. These specify that the`i`

th point has Cartesian coordinates`(x[i],y[i])`

, and lies on segment number`seg[i]`

of the network`L`

, at a fractional position`tp[i]`

along that segment (with`tp=0`

representing one endpoint and`tp=1`

the other endpoint of the segment).`x,y`

are missing and`seg,tp`

are vectors of equal length as described above.`seg,tp`

are`NULL`

, and`x,y`

are data in a format acceptable to`xy.coords`

specifying the Cartesian coordinates.Only the arguments

`x`

and`L`

are given, and`x`

is a data frame with one of the following types:two columns labelled

`seg,tp`

interpreted as local coordinates on the network.two columns labelled

`x,y`

interpreted as Cartesian coordinates.four columns labelled

`x,y,seg,tp`

interpreted as Cartesian coordinates and local coordinates.

##### Value

A point pattern
on a linear network (object of class `"lpp"`

).

##### See Also

`lpp`

.

##### Examples

```
# NOT RUN {
A <- as.psp(simplenet)
X <- runifpointOnLines(10, A)
is.ppp(X)
Y <- as.lpp(X, L=simplenet)
# }
```

*Documentation reproduced from package spatstat, version 1.64-1, License: GPL (>= 2)*