# scalardilate

##### Apply Scalar Dilation

Applie scalar dilation to a plane geometrical object, such as a point pattern or a window, relative to a specified origin.

##### Usage

`scalardilate(X, f, ...)` ## S3 method for class 'owin':
scalardilate(X, f, \dots, origin=NULL)

## S3 method for class 'ppp':
scalardilate(X, f, \dots, origin=NULL)

## S3 method for class 'default':
scalardilate(X, f, \dots)

##### Arguments

- X
- Any suitable dataset representing a two-dimensional
object, such as a point pattern (object of class
`"ppp"`

), or a window (object of class`"owin"`

). - f
- Scalar dilation factor. A finite number greater than zero.
- ...
- Ignored by the methods.
- origin
- Origin for the scalar dilation. Either a vector of 2 numbers,
or one of the character strings
`"centroid"`

,`"midpoint"`

or`"bottomleft"`

(partially matched).

##### Details

This command performs scalar dilation of the object `X`

by the factor `f`

relative to the origin specified by
`origin`

.

The function `scalardilate`

is generic, with methods for
windows (class `"owin"`

) and point patterns (class `"ppp"`

)
and a default method.

If the argument `origin`

is not given,
then every spatial coordinate is multiplied by the factor `f`

.

If `origin`

is given, then scalar dilation is performed
relative to the specified origin. Effectively, `X`

is shifted
so that `origin`

is moved to `c(0,0)`

, then scalar dilation
is performed, then the result is shifted so that `c(0,0)`

is
moved to `origin`

.

This command is a special case of an affine transformation:
see `affine`

.

##### Value

- Another object of the same type, representing the result of applying the scalar dilation.

##### See Also

##### Examples

```
plot(letterR)
plot(scalardilate(letterR, 0.7, origin="bot"), col="red", add=TRUE)
```

*Documentation reproduced from package spatstat, version 1.28-1, License: GPL (>= 2)*