tor.shift: Toroidal shift on a point data set
Description
Perform a toroidal shift on a point data setUsage
tor.shift(pts,xsh=0.0,ysh=0.0,rect)
Arguments
pts
The point data set to shift
xsh
Amount to shift along the x-axis
ysh
Amount to shift along the y-axis
rect
A rectangle defining the region for the toroidal map. If not given,
the bounding box of pts is used.
Value
- A point data set like
pts, but after application of a toroidal
shift along the x and y axes.
METHOD
The planar region defined by rect
is assumed connected at its top and bottom edges, and at its left and
right sides. A shift of xsh and ysh is applied to the
points and the resulting set of points returned.References
Rowlingson, B. and Diggle, P. 1993 Splancs: spatial point pattern analysis
code in S-Plus. Computers and Geosciences, 19, 627-655;
the original sources can be accessed at:
http://www.maths.lancs.ac.uk/~rowlings/Splancs/. See also Bivand, R. and
Gebhardt, A. 2000 Implementing functions for spatial statistical analysis
using the R language. Journal of Geographical Systems, 2, 307-317.