as.ppp {maptools}R Documentation

coercion between sp objects and spatstat objects

Description

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.

Usage

as.SpatialPoints.ppp(from)
as.SpatialPointsDataFrame.ppp(from)
as.SpatialGridDataFrame.ppp(from)
as.SpatialGridDataFrame.im(from)
as.psp.Line(from, ..., window=NULL, marks=NULL, fatal)
as.psp.Lines(from, ..., window=NULL, marks=NULL, fatal)
as.psp.SpatialLines(from, ..., window=NULL, marks=NULL, fatal)
as.psp.SpatialLinesDataFrame(from, ..., window=NULL, marks=NULL, fatal)

Arguments

from object to coerce from
... other arguments to be passed through
window window as defined in the spatstat package
marks marks as defined in the spatstat package
fatal formal coercion argument

Methods

coerce
signature(from = "SpatialPoints", to = "ppp")
coerce
signature(from = "SpatialPointsDataFrame", to = "ppp")
coerce
signature(from = "Line", to = "psp")
coerce
signature(from = "Lines", to = "psp")
coerce
signature(from = "SpatialLines", to = "psp")
coerce
signature(from = "SpatialLinesDataFrame", to = "psp")
coerce
signature(from = "SpatialGridDataFrame", to = "ppp")
coerce
signature(from = "SpatialPolygons", to = "owin")
coerce
signature(from = "SpatialPixelsDataFrame", to = "owin")
coerce
signature(from = "SpatialGridDataFrame", to = "owin")
coerce
signature(from = "SpatialGridDataFrame", to = "im")
coerce
signature(from = "im", to = "SpatialGridDataFrame")
coerce
signature(from = "ppp", to = "SpatialGridDataFrame")
coerce
signature(from = "ppp", to = "SpatialPointsDataFrame")
coerce
signature(from = "ppp", to = "SpatialPoints")

Note

When coercing a SpatialPolygons object to an owin object, full topology checking is enabled by default. To avoid checking, set spatstat.options(checkpolygons=FALSE) (from spatstat (1.14-6)). To perform the checking later, owinpolycheck(W, verbose=TRUE).

Author(s)

Edzer Pebesma e.pebesma@geo.uu.nl, Roger Bivand

Examples

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)
data(meuse.riv)
mr <- Line(meuse.riv)
mr_psp <- as(mr, "psp")
mr_psp
plot(mr_psp)
# 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)

[Package maptools version 0.7-20 Index]