Computes the centroid (centre of mass) of a window

`centroid.owin(w, as.ppp = FALSE)`

w

A window

as.ppp

Logical flag indicating whether to return the centroid
as a point pattern (`ppp`

object)

Either a list with components `x, y`

, or a point pattern (of class
`ppp`

) consisting of a single point, giving the coordinates of the
centroid of the window `w`

.

The centroid of the window `w`

is computed.
The centroid (``centre of mass'')
is the point whose \(x\) and \(y\) coordinates
are the mean values of the \(x\) and \(y\) coordinates
of all points in the window.

The argument `w`

should be a window (an object of class
`"owin"`

, see `owin.object`

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

.

The calculation uses an exact analytic formula for the case of polygonal windows.

Note that the centroid of a window is not necessarily inside
the window, unless the window is convex.
If `as.ppp=TRUE`

and
the centroid of `w`

lies outside `w`

,
then the window of the returned point pattern
will be a rectangle containing the
original window (using `as.rectangle`

.

# NOT RUN { w <- owin(c(0,1),c(0,1)) centroid.owin(w) # returns 0.5, 0.5 w <- Window(demopat) # an irregular window cent <- centroid.owin(w, as.ppp = TRUE) wapprox <- as.mask(w) # pixel approximation of window if(interactive()) { plot(cent) # plot the window and its centroid points(centroid.owin(wapprox)) # should be indistinguishable } # }