# area.owin: Area of a Window

## Description

Computes the area of a window

## Usage

area(w) # S3 method for owin
area(w)

# S3 method for default
area(w)

# S3 method for owin
volume(x)

## Arguments

w

A window, whose area will be computed.
This should be an object of class `owin`

,
or can be given in any format acceptable to `as.owin()`

.

## Value

A numerical value giving the area of the window.

## Details

If the window `w`

is of type `"rectangle"`

or `"polygonal"`

,
the area of this rectangular window is computed by analytic geometry.
If `w`

is of type `"mask"`

the area of the discrete raster approximation of the window is
computed by summing the binary image values and adjusting for
pixel size.

The function `volume.owin`

is identical to `area.owin`

except for the argument name. It is a method for the generic function
`volume`

.

## Examples

# NOT RUN {
w <- unit.square()
area(w)
# returns 1.00000
k <- 6
theta <- 2 * pi * (0:(k-1))/k
co <- cos(theta)
si <- sin(theta)
mas <- owin(c(-1,1), c(-1,1), poly=list(x=co, y=si))
area(mas)
# returns approx area of k-gon
mas <- as.mask(square(2), eps=0.01)
X <- raster.x(mas)
Y <- raster.y(mas)
mas$m <- ((X - 1)^2 + (Y - 1)^2 <= 1)
area(mas)
# returns 3.14 approx
# }