# plot.window

##### Set up World Coordinates for Graphics Window

This function sets up the world coordinate system for a graphics
window. It is called by higher level functions such as
`plot.default`

(*after* `plot.new`

).

- Keywords
- aplot

##### Usage

`plot.window(xlim, ylim, log = "", asp = NA, …)`

##### Arguments

- xlim, ylim
numeric vectors of length 2, giving the x and y coordinates ranges.

- log
character; indicating which axes should be in log scale.

- asp
numeric, giving the

**asp**ect ratio y/x, see ‘Details’.- …
further graphical parameters as in

`par`

. The relevant ones are`xaxs`

,`yaxs`

and`lab`

.

##### Details

- asp:
If

`asp`

is a finite positive value then the window is set up so that one data unit in the x direction is equal in length to`asp`

\(\times\) one data unit in the y direction.Note that in this case,

`par("usr")`

is no longer determined by, e.g.,`par("xaxs")`

, but rather by`asp`

and the device's aspect ratio. (See what happens if you interactively resize the plot device after running the example below!)The special case

`asp == 1`

produces plots where distances between points are represented accurately on screen. Values with`asp > 1`

can be used to produce more accurate maps when using latitude and longitude.

Note that the coordinate ranges will be extended by 4% if the
appropriate graphical parameter `xaxs`

or `yaxs`

has value
`"r"`

(which is the default).

To reverse an axis, use `xlim`

or `ylim`

of the form
`c(hi, lo)`

.

The function attempts to produce a plausible set of scales if one or
both of `xlim`

and `ylim`

is of length one or the two values
given are identical, but it is better to avoid that case.

Usually, one should rather use the higher-level functions such as
`plot`

, `hist`

, `image`

, …,
instead and refer to their help pages for explanation of the
arguments.

A side-effect of the call is to set up the `usr`

, `xaxp`

and
`yaxp`

graphical parameters. (It is for the latter two that
`lab`

is used.)

##### See Also

`xy.coords`

,
`plot.xy`

,
`plot.default`

.

`par`

for the graphical parameters mentioned.

##### Examples

`library(graphics)`

```
##--- An example for the use of 'asp' :
require(stats) # normally loaded
loc <- cmdscale(eurodist)
rx <- range(x <- loc[,1])
ry <- range(y <- -loc[,2])
plot(x, y, type = "n", asp = 1, xlab = "", ylab = "")
abline(h = pretty(rx, 10), v = pretty(ry, 10), col = "lightgray")
text(x, y, labels(eurodist), cex = 0.8)
```

*Documentation reproduced from package graphics, version 3.4.0, License: Part of R 3.4.0*