leafletR (version 0.4-0)

styleGrad: Graduated styling

Description

Creates a graduated style based on an attribute.

Usage

styleGrad(prop, breaks, closure, out, style.par, style.val, leg, ...)
grads(prop, breaks, closure, out, style.par, style.val, leg, ...)

Arguments

prop

Property (attribute) of the data to be styled, as string.

breaks

A vector giving the breakpoints between the desired classes.

closure

Specifies whether class intervals are closed on the left, i.e. >=breakpoint ("left", the default) or on the right, i.e. >breakpoint ("right").

out

Handling of data outside the edges of breaks. One of 0 (left and right-closed), 1 (left-closed, right-open), 2 (left-open, right-closed) or 3 (left and right-open). Default is 0.

style.par

Styling parameter as string. One of "col" (graduated color) or "rad" (graduated radius). Graduated radius can only be applied to points.

style.val

Styling values, a vector of colors or radii applied to the classes.

leg

Legend title as string. The line break sequence \n may be used for line splitting.

...

Additional styling parameters, see styleSingle for details.

Value

See Also

styleSingle, styleCat, leaflet

Examples

## Not run: 
# # prepare data
# data(quakes)
# qks <- toGeoJSON(data=quakes, dest=tempdir())
# 
# # prepare style
# range(quakes$mag)	# gives 4.0 and 6.4
# sty <- styleGrad(prop="mag", breaks=seq(4, 6.5, by=0.5), 
#   style.val=rev(heat.colors(5)), leg="Richter Magnitude")
# 
# # create map
# map <- leaflet(data=qks, dest=tempdir(), 
#   title="Fiji Earthquakes", style=sty)
# 
# # find class intervals and colors using the classInt package
# library(classInt)
# brks <- classIntervals(quakes$mag, 7)
# cols <- findColours(brks, c("yellow", "red", "darkred"))
# sty <- styleGrad(prop="mag", breaks=brks, style.val=cols, 
#   leg="Richter Magnitude")
# map <- leaflet(data=qks, dest=tempdir(), 
#    title="Fiji Earthquakes", style=sty)
# 
# # intervals closed right
# # note the gray points on the map: magnitude of 4 is outside the breaks
# # (which are >4.0, >4.5, >5.0, >5.5, >6.0 and >6.5)
# sty <- styleGrad(prop="mag", breaks=seq(4, 6.5, by=0.5), closure="right", 
#   style.val=rev(heat.colors(5)), leg="Richter Magnitude")
# map <- leaflet(data=qks, dest=tempdir(), 
#   title="Fiji Earthquakes", style=sty)
# 
# # handle outliers
# sty <- styleGrad(prop="mag", breaks=seq(5, 6.4, by=0.2), 
#   out=2, style.val=c("white", rev(heat.colors(7))), leg="Richter Magnitude")
# map <- leaflet(data=qks, dest=tempdir(), 
#   title="Fiji Earthquakes", style=sty)
# 
# # graduated radius
# sty <- styleGrad(prop="mag", breaks=seq(4, 6.5, by=0.5), style.par="rad", 
#   style.val=c(2,5,9,14,20), leg="Richter Magnitude")
# map <- leaflet(data=qks, dest=tempdir(), 
#   title="Fiji Earthquakes", style=sty)
# 
# # additional styling parameters
# peak <- toGeoJSON(data=system.file(package="leafletR", "files", 
#   "peak_sk.kmz"), dest=tempdir())  # httr package required
# sty <- styleGrad(prop="Name", breaks=seq(750, 2500, by=250), out=3, 
#   style.val=terrain.colors(9), leg="Elevation", 
#   col=NA, fill.alpha=1, rad=3)
# map <- leaflet(data=peak, dest=tempdir(), title="Peak elevation", 
#   base.map="mqsat", style=sty, popup="Name")
# ## End(Not run)