I have a data frame 'mydata.final' (see below) that contains US counties and a continuous numeric variable 'Mean.Wait' that ranges from zero to 10 or so. I also created variable 'wait' that is based on the 'Mean.Wait' and takes on discrete values from 1 (lowest values on 'Mean.Wait') to 5 (highest values on 'Mean.Wait').
I can create a map of the US with the counties colored based on the values of 'wait' using R package 'maps': ################################################################# ### Generating an artificial data file: ################################################################# library(maps) mydata.final <- data.frame(county = (map('county', plot = FALSE)$names), stringsAsFactors = F) ### My numeric variable: set.seed(123) mydata.final$Mean.Wait <- runif(nrow(mydata.final)) * 10 ### Introducing NAs to mimic my real data set: set.seed(1234) mydata.final$Mean.Wait[sample(1:nrow(mydata.final), 1500)] <- NA ### Cutting the original numeric variable into categories ### because I don't know how to color based on 'Mean.Wait': mydata.final$wait <- cut(mydata.final$Mean.Wait, breaks = 5) levels(mydata.final$wait) <- 1:5 mydata.final$wait <- as.numeric(as.character(mydata.final$wait)) #################################################################### Building a US map based on 'wait' (5 categories) ################################################################# ### Creating my 5 colors: pal <- colorRampPalette(c("yellow", "red")) allcolors <- pal(5) ### Looking at my 5 colors: barplot(1:5, rep(1,5), col = allcolors, horiz = T) ### Builiding the US map using 5 categories in 'wait': map('county', fill = TRUE, col = allcolors[mydata.final$wait], resolution = 0, lty = 0, bg = "transparent") map('state', lwd=1, add=TRUE) My goal is: instead of splitting 'Mean.Wait' into 5 ordered categories ('wait'), I'd like to color the counties on the map based on the intensity of my (continuous) 'Mean.Wait'. What would be the way to do it and maybe even to add a legend? Thanks a lot! -- Dimitri Liakhovitski ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.