# The package maps is already in R.
library(maps)

# see more examples page 6
# https://cran.r-project.org/web/packages/maps/maps.pdf

# https://github.com/tonmcg/County_Level_Election_Results_12-16/blob/master/2016_US_County_Level_Presidential_Results.csv
# https://raw.githubusercontent.com/tonmcg/County_Level_Election_Results_12-16/master/2016_US_County_Level_Presidential_Results.csv

df=read.csv("USCountyLevelPresidentialResults2016.csv",header = T,sep=",")
dfIL=subset(df,state_abbr=="IL")
dim(dfIL)
# 102 11

map("county","Illinois",plot=T,fill=T,col="red")
map("county","Illinois",plot=T,fill=T,col=2)

# HW color the counties first in two different colors; sequence of colors; dependent on percentage of votes; number of votes

mycolors=rep(2,times=102)
mycolors[dfIL[,5]>=0.5]=3
map("county","Illinois",plot=T,fill=T,col=mycolors)

# The following link contains presidential results for 2008, 2012, 2016.
# https://github.com/tonmcg/County_Level_Election_Results_12-16
# Click on the link for results 2008-2016 to download the file; 
# otherwise it can be found in the coursework folder in the virtual desktop.

df=read.csv("USCountyLevelPresidentialResults0816.csv")

# There is no column for states but the first column is FIPS codes.
# Each county in Illinois has a five digit FIPS code beginning with 17 and
# ending with values between 000 and 203.
# https://en.wikipedia.org/wiki/List_of_counties_in_Illinois