rotate sp.objects in spplot?

Hi everyone,

Just wondering if anyone knows how to rotate objects in spplot. Using 
the script below, let's say I wanted to rotate the north arrow by 12 
degrees... any ideas? Thanks!

library(sp)
library(lattice) # required for trellis.par.set():
trellis.par.set(sp.theme()) # sets color ramp to bpy.colors()

data(meuse)
coordinates(meuse)=~x+y

scale = list("SpatialPolygonsRescale", layout.scale.bar(),
       offset = c(178600,332990), scale = 500, fill=c("transparent","black"))
text1 = list("sp.text", c(178600,333090), "0")
text2 = list("sp.text", c(179100,333090), "500 m")
arrow = list("SpatialPolygonsRescale", layout.north.arrow(),
       offset = c(178750,332500), scale = 400)
## points plot with scale bar, scale bar text, north arrow and title:
spplot(meuse, "zinc", do.log=T,
       key.space=list(x=0.1,y=0.93,corner=c(0,1)),
       sp.layout=list(scale,text1,text2,arrow),
       main = "Zinc (top soil)")

Hi everyone,

Just wondering if anyone knows how to rotate objects in spplot. Using
the script below, let's say I wanted to rotate the north arrow by 12
degrees... any ideas? Thanks!

library(sp)
library(lattice) # required for trellis.par.set():
trellis.par.set(sp.theme()) # sets color ramp to bpy.colors()

data(meuse)
coordinates(meuse)=~x+y

scale = list("SpatialPolygonsRescale", layout.scale.bar(),
       offset = c(178600,332990), scale = 500, fill=c("transparent","black"))
text1 = list("sp.text", c(178600,333090), "0")
text2 = list("sp.text", c(179100,333090), "500 m")
arrow = list("SpatialPolygonsRescale", layout.north.arrow(),
       offset = c(178750,332500), scale = 400)
## points plot with scale bar, scale bar text, north arrow and title:
spplot(meuse, "zinc", do.log=T,
       key.space=list(x=0.1,y=0.93,corner=c(0,1)),
       sp.layout=list(scale,text1,text2,arrow),
       main = "Zinc (top soil)")

Thanks very much Roger!

Is it possible to also rotate sp.text with elide?

Myles

-----Original Message-----
From: Roger Bivand [mailto:Roger.Bivand at nhh.no]
Sent: September-28-11 3:42 AM
To: Myles Falconer
Cc: 'r-sig-geo at r-project.org'
Subject: Re: [R-sig-Geo] rotate sp.objects in spplot?

On Tue, 27 Sep 2011, Myles Falconer wrote:

Hi everyone,

Just wondering if anyone knows how to rotate objects in spplot. Using
the script below, let's say I wanted to rotate the north arrow by 12
degrees... any ideas? Thanks!

library(maptools)
?elide

So:

arrow = list("SpatialPolygonsRescale", elide(layout.north.arrow(),
  rotate=12), offset = c(178750,332500), scale = 400)

looks about OK. Do you know that your data have non-North Northings (I
guess you do!), the presumption in "Spatial" objects is that North is
aligned with the vertical axis?

Roger

library(sp)
library(lattice) # required for trellis.par.set():
trellis.par.set(sp.theme()) # sets color ramp to bpy.colors()

data(meuse)
coordinates(meuse)=~x+y

scale = list("SpatialPolygonsRescale", layout.scale.bar(),
       offset = c(178600,332990), scale = 500, fill=c("transparent","black"))
text1 = list("sp.text", c(178600,333090), "0")
text2 = list("sp.text", c(179100,333090), "500 m")
arrow = list("SpatialPolygonsRescale", layout.north.arrow(),
       offset = c(178750,332500), scale = 400)
## points plot with scale bar, scale bar text, north arrow and title:
spplot(meuse, "zinc", do.log=T,
       key.space=list(x=0.1,y=0.93,corner=c(0,1)),
       sp.layout=list(scale,text1,text2,arrow),
       main = "Zinc (top soil)")

--
Roger Bivand
Department of Economics, NHH Norwegian School of Economics,
Helleveien 30, N-5045 Bergen, Norway.
voice: +47 55 95 93 55; fax +47 55 95 95 43
e-mail: Roger.Bivand at nhh.no