data.framesSpatialPoints(coords, proj4string=CRS(as.character(NA)), bbox = NULL)
SpatialPointsDataFrame(coords, data, coords.nrs = numeric(0),
proj4string = CRS(as.character(NA)), match.ID = TRUE, bbox = NULL)data.frame; the number of rows in data
should equal the number of points in the coords objectdata the coordinates were taken from (used by coordinates<-)dimnames(coords)[[2]] is not NULL), AND data has
row.names (i.e. is a data.frame), then the SpatialPointsDataFrame
object is formed by matching the row names ofSpatialPoints returns an object of class SpatialPoints;
SpatialPointsDataFrame returns an object of class SpatialPointsDataFrame;