# transect.im

##### Pixel Values Along a Transect

Extract the pixel values of a pixel image at each point along a linear transect.

##### Usage

```
transect.im(X, ..., from="bottomleft", to="topright",
click=FALSE, add=FALSE)
```

##### Arguments

- X
A pixel image (object of class

`"im"`

).- …
Ignored.

- from,to
Optional. Start point and end point of the transect. Pairs of \((x,y)\) coordinates in a format acceptable to

`xy.coords`

, or keywords`"bottom"`

,`"left"`

,`"top"`

,`"right"`

,`"bottomleft"`

etc.- click
Optional. Logical value. If

`TRUE`

, the linear transect is determined interactively by the user, who clicks two points on the current plot.- add
Logical. If

`click=TRUE`

, this argument determines whether to perform interactive tasks on the current plot (`add=TRUE`

) or to start by plotting`X`

(`add=FALSE`

).

##### Details

The pixel values of the image `X`

along a line segment
will be extracted. The result is a function table (`"fv"`

object)
which can be plotted directly.

If `click=TRUE`

, then the user is prompted to click two points on
the plot of `X`

. These endpoints define the transect.

Otherwise, the transect is defined by the endpoints
`from`

and `to`

. The default is a diagonal transect from
bottom left to top right of the frame.

##### Value

An object of class `"fv"`

which can be plotted.

##### See Also

##### Examples

```
# NOT RUN {
Z <- density(redwood)
plot(transect.im(Z))
# }
# NOT RUN {
if(FALSE) {
plot(transect.im(Z, click=TRUE))
}
# }
```

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