# nestsplit

##### Nested Split

Applies two splitting operations to a point pattern, producing a list of lists of patterns.

##### Usage

`nestsplit(X, …)`

##### Arguments

- X
Point pattern to be split. Object of class

`"ppp"`

.- …
Data determining the splitting factors or splitting regions. See Details.

##### Details

This function splits the point pattern `X`

into several
sub-patterns using `split.ppp`

, then splits each of the
sub-patterns into sub-sub-patterns using `split.ppp`

again.
The result is a hyperframe containing the sub-sub-patterns
and two factors indicating the grouping.

The arguments `…`

determine the two splitting factors
or splitting regions. Each argument may be:

a factor (of length equal to the number of points in

`X`

)the name of a column of marks of

`X`

(provided this column contains factor values)a tessellation (class

`"tess"`

)a pixel image (class

`"im"`

) with factor valuesa window (class

`"owin"`

)identified by name (in the form

`name=value`

) as one of the formal arguments of`quadrats`

or`tess`

The arguments will be processed to yield a list of two
splitting factors/tessellations. The splits will be applied
to `X`

consecutively to produce the sub-sub-patterns.

##### Value

A hyperframe with three columns. The first column contains the sub-sub-patterns. The second and third columns are factors which identify the grouping according to the two splitting factors.

##### See Also

##### Examples

```
# NOT RUN {
# factor and tessellation
Nft <- nestsplit(amacrine, marks(amacrine), quadrats(amacrine, 3, 1))
Ntf <- nestsplit(amacrine, quadrats(amacrine, 3, 1), marks(amacrine))
Ntf
# two factors
big <- with(marks(betacells), area > 300)
Nff <- nestsplit(betacells, "type", factor(big))
# two tessellations
Tx <- quantess(redwood, "x", 4)
Td <- dirichlet(runifpoint(5, Window(redwood)))
Ntt <- nestsplit(redwood, Td, Tx)
Ntt2 <- nestsplit(redwood, Td, ny=3)
# }
```

*Documentation reproduced from package spatstat, version 1.56-1, License: GPL (>= 2)*