Plot methods for spatial data with attributes
Lattice (trellis) plot methods for spatial data with attributes methods
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()
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
(points) is used; for further control custom panel functions can be supplied that call one of these panel functions, but do read below how the argument sp.layout may help
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 on panel i,j, pass the value c(i,j)
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
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
Missing values in the attributes are (currently) not allowed.
spplot.grid, spplot.polygons and spplot.points are S4 methods for spplot; see spplot-methods .
Useful arguments that can be passed as ... are:
layout: integer; for the layout of panels (cols,rows)pretty: logical; choose colour breaks at pretty numbers?at: specify at which values colours changeas.table: logical; start drawing panels upper-left instead of lower-leftpage: to add marks to each plotted pagefor useful values see the appropriate documentation of xyplot
(in case of points), and levelplot (otherwise).
If obj is of SpatialPointsDataFrame, the following options are useful to pass:
key.space: character: "bottom", "right", "left" or "right" to denote key location, or list: see argument key in the help for xyplot what the options arelegendEntries: character; array with key legend (text) entries; suitable defaults obtained from datacuts: number of cuts, or, for objects of class SpatialPointsDataFrame only, the actual cuts to usedo.log: logical; if TRUE use log-linear scale to divide range in equal cuts, else use a linear scale if cuts is only number of cutspch: integer; plotting character to use; defaults to 16 if fill is TRUE, else 1cex: numeric; character expansion, proportional to default value of 1fill: logical; use filled circles?layout.north.arrow and layout.scale.bar can be used
to set a north arrow or scale bar.
The sp.layout argument is either a single layout item, or a list
with one or more layout items. A layout item is one of
a list with one or more Spatial* objects, along with style arguments like col, lty, pch, fill etc.
a list with its first argument the layout function or the name of the layout function to be called: sp.points for SpatialPoints, sp.polygons for SpatialPolygons object, sp.lines
for a SpatialLines object, and sp.text for text to place. The second argument contains the object (or text) to be plotted; remaining arguments are passed to the corresponding panel.* functions.
The order of items in sp.layout matters; objects are drawn in the
order they appear. With respect to obj, default plot order and
precedence of sp.layout items is as follows: for points and
lines, sp.layout items are drawn over (after) obj; for
grids and polygons, sp.layout items are drawn behind (before)
obj. Transparency may further help making multiple things
visible. Adding a first argument to a layout item overrides its
default plotting order with respect to obj:
Special control elements of sp.layout items:
first: logical; 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).which: integer; 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.sp.theme returns a lattice theme; use, after loading package
lattice, the command trellis.par.set(sp.theme())
after a device is opened or changed to make this work. Currently, this only sets the colors to bpy.colors .
If the attributes to be plotted are of type factor, spplot tries to create a legend that reflects this. In this case, the color ramp passed needs to be of the same length as the number of factor levels. The factor levels are derived from the first map; subsequent factors with different factor levels result in an error.
xyplot , levelplot , panel.identify to identify objects
Edzer Pebesma, edzer.pebesma@uni-muenster.de
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))