# Polygon area

### Description

An all-R routine that computes area of all
polygons in a `SpatialPolygons*`

object,
taking account of holes.

### Usage

1 | ```
polygonArea(x)
``` |

### Arguments

`x` |
A spatial object inheriting from |

### Details

Provides the same answer as `rgeos::gArea`

, but is
all-R (does not require rgeos Java library) and does not
fire a warning if `x`

is un-projected (i.e., lat-long).

### Value

Area of all polygons in `x`

, taking account of holes.
Units of area are squared units of coordinates in `x`

. E.g.,
square meters if coordinates in `x`

are UTM meters, square
decimal degrees if coordinates in `x`

are lat-long decimal
degrees.

### Author(s)

Trent McDonald

### See Also

`sp::SpatialPolygons-class`

### Examples

1 2 | ```
# Area of Washington state, in hectares
a <- polygonArea( WA ) / (100*100)
``` |