Mapping variables based on STFID values

Question

This quest is an extention of a question that I made earlier today but since it's migration to GIS I haven't been able to comment on my older post. My earlier post is : Mapping Kansas City based on X and Y Coordinates in R

I have found a more specific coordinate system known as STFID. From what I have researched about STFID the larger the number the more specific of a locale the point equals. Each STFID contains 15 digits, which I believe is sufficient enough to account for each block in Kansas City, MO.

Is there a way that I can map information in R when using this STFID value?

Answer 1

As a general point ggplot2 seems to understand shapefiles that contain STFIDs, such as those used in the US Census Tract data. Using that data for San Francisco I came up with this:

If your CSV file has two STFID coordinates for each line then you might be able to plot it with a variation on the code below. Until you show us some data it's hard to be sure.

library(rgdal)
library(ggplot2)
# source URL for San Francisco zipped shapefile and related:
# http://goo.gl/B4uwri

work.dir <- "your_work_dir" # no trailing slash
mysp <- readOGR(work.dir, layer = "census2000_tracts_nowater")

mydf <- fortify(mysp, region = 'STFID') # convert to data frame for ggplot
mydf$fakedata <- runif(nrow(mydf), 1, 10) # create random data

ggplot(data = mydf, aes(x = long, y = lat, fill = fakedata, group = group)) +
    geom_polygon(colour = "black") +
    scale_x_continuous(limits = c(5970000, 6030000)) + # constrain the scale
    coord_equal() +
    theme(legend.position = "none")