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sp (version 1.2-1)

spplot: Plot methods for spatial data with attributes

Description

Lattice (trellis) plot methods for spatial data with attributes

Usage

spplot(obj, ...)
spplot.grid(obj, zcol = names(obj), ..., names.attr, scales = list(draw = FALSE),
 xlab = NULL, ylab = NULL, aspect = mapasp(obj,xlim,ylim),
 panel = panel.gridplot, sp.layout = NULL, formula, xlim = bbox(obj)[1, ],
 ylim = bbox(obj)[2, ], checkEmptyRC = TRUE, col.regions = get_col_regions())
spplot.polygons(obj, zcol = names(obj), ..., names.attr, scales = list(draw = FALSE),
 xlab = NULL, ylab = NULL, aspect = mapasp(obj,xlim,ylim),
 panel = panel.polygonsplot, sp.layout = NULL, formula, xlim = bbox(obj)[1, ],
 ylim = bbox(obj)[2, ], col.regions = get_col_regions())
spplot.points(obj, zcol = names(obj), ..., names.attr, scales = list(draw = FALSE),
 xlab = NULL, ylab = NULL, aspect = mapasp(obj,xlim,ylim),
 panel = panel.pointsplot, sp.layout = NULL, identify = FALSE, formula,
 xlim = bbexpand(bbox(obj)[1, ], 0.04), ylim = bbexpand(bbox(obj)[2, ], 0.04),
 edge.col = "transparent", colorkey = FALSE, col.regions = get_col_regions())
mapLegendGrob(obj, widths = unit(1, "cm"), heights = unit(1, "cm"),
	fill = "black", just = "right")
sp.theme(set = FALSE, regions = list(col = bpy.colors(100)), ...)
layout.north.arrow(type = 1)
layout.scale.bar(height = 0.05)
spplot.locator(n = 512, type = "n", ...)
set_col_regions(value)
get_col_regions()

Arguments

obj
object of class extending Spatial-class
zcol
character; attribute name(s) or column number(s) in attribute table
names.attr
names to use in panel, if different from zcol names
scales
scales argument to be passed to Lattice plots; use list(draw = TRUE) to draw axes scales; see xyplot for full options
...
other arguments passed to levelplot (grids, polygons) or xyplot (points)
xlab
label for x-axis
ylab
label for y-axis
aspect
aspect ratio for spatial axes; defaults to "iso" (one unit on the x-axis equals one unit on the y-axis) but may be set to more suitable values if the data are e.g. if coordinates are latitude/longitude
panel
depending on the class of obj, panel.polygonsplot (for polygons or lines), panel.gridplot (grids) or panel.pointsplot (p
sp.layout
NULL or list; see notes below
identify
if not FALSE, identify plotted objects (currently only working for points plots). Labels for identification are the row.names of the attribute table row.names(as.data.frame(obj)). If TRUE, identify on panel (1,1); for identifying
formula
optional; may be useful to plot a transformed value. Defaults to z~x+y for single and z~x+y|name for multiple attributes; use e.g. exp(x)~x+y|name to plot the exponent of the z-variable
xlim
numeric; x-axis limits
ylim
numeric; y-axis limits
edge.col
color of symbol edge
colorkey
if FALSE, use symbol key; if TRUE, use continuous, levelplot-like colorkey; if list, follow syntax of argument colorkey in levelplot (see below for an example)
widths
width of grob
heights
heights of grob
fill
fill color of grob
just
grob placement justification
set
logical; if TRUE, trellis.par.set is called, else a list is returned that can be passed to trellis.par.set()
regions
color ramp for the theme
height
height of scale bar; width is 1.0
n
see locator
type
see locator
checkEmptyRC
logical; if TRUE, a check is done to see if empty rows or columns are present, and need to be taken care of. Setting to FALSE may improve speed.
col.regions
vector with fill colours; in case the variable to be plotted is a factor, this vector should have length equal to the number of factor levels
value
vector with color values, default for col.regions

Value

  • spplot returns a lattice plot of class "trellis", if you fail to "see" it, explicitly call print(spplot(...)). If identify is TRUE, the plot is plotted and the return value is a vector with row names of the selected points.

    spplot.locator returns a matrix with identified point locations; use trellis.focus first to focus on a given panel.

    get_col_regions returns the default value for col.regions

code

trellis.par.set(sp.theme())

describe

  • firstlogical; should the layout item be drawn before the obj (TRUE), or after (FALSE)? This overrides the default order (points and lines in front, polygons and grids behind).
  • whichinteger; controls to which panel a layout item should be added. If which is present in the main, top-level list it applies to all layout items; in sub-lists with layout items it denotes the (set of) panel(s) in which the layout item should be drawn. Without a which item, layout items are drawn in each panel.

References

http://rspatial.r-forge.r-project.org/gallery/

See Also

xyplot, levelplot, panel.identify to identify objects

Examples

Run this code
library(lattice)
trellis.par.set(sp.theme()) # sets bpy.colors() ramp
demo(meuse, ask = FALSE, echo = FALSE)
l2 = list("SpatialPolygonsRescale", layout.north.arrow(), offset = c(181300,329800), 
	scale = 400)
l3 = list("SpatialPolygonsRescale", layout.scale.bar(), offset = c(180500,329800), 
	scale = 500, fill=c("transparent","black"))
l4 = list("sp.text", c(180500,329900), "0")
l5 = list("sp.text", c(181000,329900), "500 m")

spplot(meuse, c("ffreq"), sp.layout=list(l2,l3,l4,l5), col.regions= "black", 
	pch=c(1,2,3), key.space=list(x=0.1,y=.95,corner=c(0,1)))
spplot(meuse, c("zinc", "lead"), sp.layout=list(l2,l3,l4,l5, which = 2),
	key.space=list(x=0.1,y=.95,corner=c(0,1)))
# plotting factors:
meuse$f = factor(sample(letters[6:10], 155, replace=TRUE),levels=letters[1:10])
meuse$g = factor(sample(letters[1:5], 155, replace=TRUE),levels=letters[1:10])
spplot(meuse, c("f","g"), col.regions=bpy.colors(10))

if (require(RColorBrewer)) {
	spplot(meuse, c("ffreq"), sp.layout=list(l2,l3,l4,l5),
		col.regions=brewer.pal(3, "Set1"))
}

meuse.grid$g = factor(sample(letters[1:5], 3103, replace=TRUE),
	levels=letters[1:10])
meuse.grid$f = factor(sample(letters[6:10], 3103, replace=TRUE),
	levels=letters[1:10])
spplot(meuse.grid, c("f","g"), col.regions=bpy.colors(10))

# example modifying colorkey for points:
spplot(meuse["dist"], colorkey = list(
	right = list( # see ?levelplot in package trellis, argument colorkey:
		fun = draw.colorkey, 
		args = list(
			key = list(
				at = seq(0, 1, .1), # colour breaks
				col = bpy.colors(11), # colours
				labels = list(
					at = c(0, .2, .4, .6, .8, 1), 
					labels = c("0x", "20x", "40x", "60x", "80x", "100x")
				)
			)
		)
	)
))
l6 = list(meuse.grid["dist"], col = grey(seq(.5,.9,length.out=10)))
spplot(meuse, c("zinc", "lead"), sp.layout = l6)
spplot(meuse, c("zinc", "lead"), 
	sp.layout = list(meuse.grid, meuse.riv, col = 'grey'))

#  Custom legend placement, taken from 
# http://stackoverflow.com/questions/29344692/custom-placement-of-spplot-legend-in-the-map
s <- spplot(meuse.grid[,'dist'], colorkey = list(space = "left", height = 0.4))

args <- s$legend$left$args$key

## Prepare list of arguments needed by `legend=` argument (as described in ?xyplot)
library(lattice) # draw.colorkey
legendArgs <- list(fun = draw.colorkey,
                   args = list(key = args),
                   corner = c(0.05,.75))

## Call spplot() again, this time passing in to legend the arguments
## needed to print a color key
spplot(meuse.grid[,'dist'], colorkey = FALSE,
       legend = list(inside = legendArgs))

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