Allows to control the size of the arrows in geom_arrow.
Highly experimental.

```
scale_mag(
name = ggplot2::waiver(),
n.breaks = 1,
breaks = ggplot2::waiver(),
oob = no_censor,
...
)
scale_mag_continuous(
name = ggplot2::waiver(),
n.breaks = 1,
breaks = ggplot2::waiver(),
oob = no_censor,
...
)
```

## Arguments

- name
The name of the scale. Used as the axis or legend title. If
`waiver()`

, the default, the name of the scale is taken from the first
mapping used for that aesthetic. If `NULL`

, the legend title will be
omitted.

- n.breaks
An integer guiding the number of major breaks. The algorithm
may choose a slightly different number to ensure nice break labels. Will
only have an effect if `breaks = waiver()`

. Use `NULL`

to use the default
number of breaks given by the transformation.

- breaks
One of:

`NULL`

for no breaks

`waiver()`

for the default breaks computed by the
transformation object

A numeric vector of positions

A function that takes the limits as input and returns breaks
as output (e.g., a function returned by `scales::extended_breaks()`

).
Note that for position scales, limits are provided after scale expansion.
Also accepts rlang lambda function notation.

- oob
One of:

Function that handles limits outside of the scale limits
(out of bounds). Also accepts rlang lambda
function notation.

The default (`scales::censor()`

) replaces out of
bounds values with `NA`

.

`scales::squish()`

for squishing out of bounds values into range.

`scales::squish_infinite()`

for squishing infinite values into range.

- ...
Other arguments passed on to `scale_(x|y)_continuous()`

## Examples

```
library(ggplot2)
g <- ggplot(seals, aes(long, lat)) +
geom_vector(aes(dx = delta_long, dy = delta_lat), skip = 2)
g + scale_mag("Seals velocity")
g + scale_mag("Seals velocity", limits = c(0, 1))
```