Learn R Programming

spatstat.explore (version 3.2-5)

radcumint: Radial Cumulative Integral

Description

Compute the cumulative integral of an image over increasing radial distances from the origin.

Usage

radcumint(X, ..., origin, Xname, result = c("fv", "im"))

Value

An object of class "fv" or "im", with the same coordinate units as X.

Arguments

X

A pixel image (object of class "im") with numerical or logical values.

...

Ignored.

origin

Optional. Origin about which the rotations should be performed. Either a numeric vector or a character string as described in the help for shift.owin.

Xname

Optional name for X to be used in the function labels.

result

Character string specifying the kind of result required: either a function object or a pixel image.

Author

Adrian Baddeley Adrian.Baddeley@curtin.edu.au, Rolf Turner rolfturner@posteo.net and Ege Rubak rubak@math.aau.dk.

Details

This command computes, for each possible distance \(r\), the integral of the pixel values lying inside the disc of radius \(r\) centred at the origin.

If result="fv" (the default) the result is a function object f of class "fv". For each value of radius \(r\), the function value f(r) is the integral of X over the disc of radius \(r\).

If result="im" the result is a pixel image, with the same dimensions as X. At a given pixel, the result is equal to f(r) where r is the distance from the given pixel to the origin. That is, at any given pixel, the resulting value is the integral of X over the disc centred at the origin whose boundary passes through the given pixel.

See Also

rotmean, spatialcdf

Examples

Run this code
   D <- density(redwood)
   plot(radcumint(D))
   plot(radcumint(D, result="im"))

Run the code above in your browser using DataLab