# plot.yardstick

##### Plot a Yardstick or Scale Bar

Plots an object of class `"yardstick"`

.

##### Usage

```
# S3 method for yardstick
plot(x, …,
angle = 20, frac = 1/8,
split = FALSE, shrink = 1/4,
pos = NULL,
txt.args=list(),
txt.shift=c(0,0),
do.plot = TRUE)
```

##### Arguments

- x
Object of class

`"yardstick"`

to be plotted. This object is created by the command`yardstick`

.- …
Additional graphics arguments passed to

`segments`

to control the appearance of the line.- angle
Angle between the arrows and the line segment, in degrees.

- frac
Length of arrow as a fraction of total length of the line segment.

- split
Logical. If

`TRUE`

, then the line will be broken in the middle, and the text will be placed in this gap. If`FALSE`

, the line will be unbroken, and the text will be placed beside the line.- shrink
Fraction of total length to be removed from the middle of the line segment, if

`split=TRUE`

.- pos
Integer (passed to

`text`

) determining the position of the annotation text relative to the line segment, if`split=FALSE`

. Values of 1, 2, 3 and 4 indicate positions below, to the left of, above and to the right of the line, respectively.- txt.args
Optional list of additional arguments passed to

`text`

controlling the appearance of the text. Examples include`adj`

,`srt`

,`col`

,`cex`

,`font`

.- txt.shift
Optional numeric vector of length 2 specifying displacement of the text position relative to the centre of the yardstick.

- do.plot
Logical. Whether to actually perform the plot (

`do.plot=TRUE`

).

##### Details

A yardstick or scale bar is a line segment, drawn on any spatial graphics display, indicating the scale of the plot.

The argument `x`

should be an object of class `"yardstick"`

created by the command `yardstick`

.

##### Value

A window (class `"owin"`

) enclosing the plotted graphics.

##### See Also

##### Examples

```
# NOT RUN {
plot(owin(), main="Yardsticks")
ys <- yardstick(as.psp(list(xmid=0.5, ymid=0.1, length=0.4, angle=0),
window=owin(c(0.2, 0.8), c(0, 0.2))),
txt="1 km")
plot(ys)
ys <- shift(ys, c(0, 0.3))
plot(ys, angle=90, frac=0.08)
ys <- shift(ys, c(0, 0.3))
plot(ys, split=TRUE)
# }
```

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