mapColorRamp: Function: Maps a sequential color theme

In TexMix: Supporting Functions and Data for Geo-Spatial Analytics Courses at UTDallas, Texas

Description

mapColorRamp generates a map with a sequential theme of an interval scaled variable

Usage

mapColorRamp(var.name, shape, breaks=8, map.title="",
                    legend.title=deparse(substitute(var.name)),
                    legend.pos="bottomleft", legend.cex=1, add.to.map=FALSE)

Arguments

var.name	A variable to be mapped in a bipolar theme. If it is in a data-frame, then the data-frame must be refered to, e.g., df$var
shape	An existing spatial polygon or spatial polygon data-frame
breaks	Number of qunatiles. It needs to range the range of 3 to 9
map.title	Character string with map title
legend.title	Character string with legend title (default=var.name)
legend.pos	Location of legend in the map frame (default="bottomleft")
legend.cex	Relative font size of the legend
add.to.map	Logical to start a new map frame if FALSE or overlay onto an existing map frame if TRUE

Details

The function mapColorRamp maps an interval scaled variable by a sequetial color ramp. Quantiles values are coded in gradually increasing intensities of oranges. A legend is generated. NA's are permitted.

Value

NULL

Author(s)

Michael Tiefelsdorf <[e-mail]>

Examples

library(maptools)
validTractShp <- tractShp[!is.na(tractShp$BUYPOW), ]         # Remove 2 tracts with NA's
mapColorQual(validTractShp$CITYPERI, validTractShp,
             map.title="Cities and Peripherie in Dallas County",
             legend.title="Regions")

mapColorRamp(validTractShp$bad1500D, validTractShp, breaks=9,
             map.title="Density of Convenience Stores in Dallas County\nbw=1500 meters",
             legend.title="Junk Food")

hist(tractShp$LRRmedD)
mapBiPolar(validTractShp$LRRmedD, validTractShp, break.value=0,
           neg.breaks=5, pos.breaks=5,
           map.title="LRR: log(f(junk food),f(healthy food))\nbw=medium",
           legend.title="log relative risk")

TexMix documentation built on March 1, 2020, 5:10 p.m.