Systematic random point pattern
Generates a ``systematic random'' pattern of points in a window, consisting of a grid of equally-spaced points with a random common displacement.
rsyst(win=square(1), nx, ny=nx, dx=NULL, dy=NULL)
- A window.
An object of class
owin, or data in any format acceptable to
- Spacing of grid points in $x$ direction.
- Spacing of grid points in $y$ direction.
- Number of columns of grid points in the window.
- Number of rows of grid points in the window.
This function generates a
win. The pattern consists of a rectangular grid
of points with a random common displacement.
The grid spacing is determined by the distances
if they are present. If they are absent, then the grid spacing is
determined so that there will be
nx columns and
of grid points in the bounding rectangle of
The grid is then given a random displacement (the common displacement
of the grid points is a uniformly distributed random vector in the
tile of dimensions
Some of the resulting grid points may lie outside the window
if they do, they are deleted.
The result is a point pattern inside the window
This function is useful in creating dummy points for quadrature
quadscheme) as well as in simulating
random point patterns.
- A point pattern (object of class
X <- rsyst(nx=10) plot(X) # polygonal boundary data(letterR) X <- rsyst(letterR, 5, 10) plot(X)