as.ppp {maptools} | R Documentation |
S4-style as() coercion works from objects of S4 sp classes to spatstat S3 classes, but not the reverse. Coercion to sp classes uses direct function calls.
as.SpatialPoints.ppp(from) as.SpatialPointsDataFrame.ppp(from) as.SpatialGridDataFrame.ppp(from) as.SpatialGridDataFrame.im(from)
from |
spatstat object of class ppp or im |
signature(from = "SpatialPoints", to = "ppp")
signature(from = "SpatialPointsDataFrame", to = "ppp")
signature(from = "SpatialGridDataFrame", to = "ppp")
signature(from = "SpatialPolygons", to = "owin")
signature(from = "SpatialPixelsDataFrame", to = "owin")
signature(from = "SpatialGridDataFrame", to = "owin")
signature(from = "SpatialGridDataFrame", to = "im")
signature(from = "im", to = "SpatialGridDataFrame")
signature(from = "ppp", to = "SpatialGridDataFrame")
signature(from = "ppp", to = "SpatialPointsDataFrame")
signature(from = "ppp", to = "SpatialPoints")
When coercing a SpatialPolygons object to an owin object, full topology
checking is enabled by default. To avoid checking, set .spatstat_check
to FALSE in the global environment. This work-around may not be required
from spatstat version 2, and is used at the risk of garbled topology breaking
other functions in spatstat.
Edzer Pebesma e.pebesma@geo.uu.nl, Roger Bivand
library(spatstat) data(meuse) coordinates(meuse) = ~x+y zn1 <- as(meuse["zinc"], "ppp") zn1 plot(zn1) as(as(meuse, "SpatialPoints"), "ppp") data(meuse.grid) gridded(meuse.grid) = ~x+y mg_owin <- as(meuse.grid, "owin") zn1a <- ppp(x=zn1$x, y=zn1$y, marks=zn1$marks, window=mg_owin) zn1a plot(zn1a) rev_ppp_SP <- as.SpatialPoints.ppp(zn1a) summary(rev_ppp_SP) rev_ppp_SPDF <- as.SpatialPointsDataFrame.ppp(zn1a) summary(rev_ppp_SPDF) rev_ppp_SGDF <- as.SpatialGridDataFrame.ppp(zn1a) summary(rev_ppp_SGDF) # as.owin(meuse.grid) # --- will only work if as.owin is method... mg_owin <- as(as(meuse.grid["ffreq"], "SpatialPixelsDataFrame"), "owin") mg_owin ho_sp <- SpatialPolygons(list(Polygons(list(Polygon(cbind(c(0,1,1,0,0), c(0,0,1,1,0))), Polygon(cbind(c(0.6,0.4,0.4,0.6,0.6), c(0.2,0.2,0.4,0.4,0.2)), hole=TRUE)), ID="ho"))) plot(ho_sp, col="red", pbg="pink") ho <- as(ho_sp, "owin") plot(ho) pp <- runifpoint(500, win=ho) plot(pp) ho_orig <- owin(poly=list(list(x=c(0,1,1,0), y=c(0,0,1,1)), list(x=c(0.6,0.4,0.4,0.6), y=c(0.2,0.2,0.4,0.4)))) identical(ho, ho_orig) mg_dist <- meuse.grid["dist"] fullgrid(mg_dist) <- TRUE image(mg_dist, axes=TRUE) mg_im <- as(mg_dist, "im") plot(mg_im) mg2 <- as.SpatialGridDataFrame.im(mg_im) image(mg2, axes=TRUE)