[R-sig-Geo] SpatialCls
Edzer J. Pebesma
e.pebesma at geog.uu.nl
Fri Nov 28 17:17:52 CET 2003
Hi Barry, Roger, r-sig-geo gang,
I just checked in updates to SpatialCls on
http://sourceforge.net/projects/r-spatial/ --
I completed documentation, added tests and examples. The
whole package should pass R CMD check. Even the S4 classes
are now documented, slots and all. No vignettes yet,
still have to get into them.
The interfaces used so far are:
# The following three promote a data.frame to a SpatialDataFrame
coordinates(meuse) = ~x+y # or
coordinates(meuse) = c("x", "y") # or
coordinates(meuse) = cbind(x,y)
# after which
coordinates(meuse)
# retrieves coordinates; also:
coordinates(meuse.grid) = ~x+y # followed by
gridded(meuse.grid) = TRUE
# promotes meuse.grid to a SpatialDataFrameGrid, which has
# (and auto-detects) grid topology; it has an image method.
# then,
polygons(x) = list(pol1, pol2, pol3)
# promotes data.frame x to a SpatialPolygons, adding the
# polygon information to it, doing some basic checks
# (e.g. pol1..3 should be 2column matrix with at least 4 points,
# first and last being the same);
polygons(x) # retrieves the polygon list
data.frame(x) # retrieves the attribute values data.frame
# some elementary plot, show, formula and summary methods are present.
What else do we need, when it comes to interfaces/methods?
Enjoy the weekend,
--
Edzer
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