choroplethr (version 1.3.0)

render_choropleth: Render a choropleth

Description

Given a data.frame which contains map data and value data, render it as a choropleth using ggplot2.

Usage

render_choropleth(choropleth.df, lod, title = "", scaleName = "",
  showLabels = TRUE, states = state.abb)

Arguments

choropleth.df

A data.frame with one column named "region" and one column named "value". The variable is normally the output of bind_df_to_map.

lod

A string representing the level of detail of your data. Must be one of "state", "county" or "zip".

title

The title of the image. Defaults to "".

scaleName

The name of the scale/legend. Default to "".

showLabels

For State maps, whether or not to show labels of the states.

states

A vector of postal codes representing US states. Defaults to state.abb.

Value

• A data.frame.

See Also

get_acs_df and bind_df_to_map

Examples

library(Hmisc) # for cut2
# States with greater than 1M residents
df     = get_acs_df("B01003", "state") # population
df.map = bind_df_to_map(df, "state")
df.map$value = cut2(df.map$value, cuts=c(0,1000000,Inf))
render_choropleth(df.map, "state", "States with a population over 1M", "Population")

# Counties with greater than or greater than 1M residents
df     = get_acs_df("B01003", "county") # population
df.map = bind_df_to_map(df, "county")
df.map$value = cut2(df.map$value, cuts=c(0,1000000,Inf))
render_choropleth(df.map, "county", "Counties with a population over 1M", "Population")

# ZIP codes in California where median age is between 20 and 30
df       = get_acs_df("B01002", "zip") # median age
df       = df[df$value >= 20 & df$value <= 30, ]
df$value = cut2(df$value, g=3) # 3 equally-sized groups
df.map   = bind_df_to_map(df, "zip")
render_choropleth(df.map,
                 "zip",
                 title = "CA Zip Codes by Age",
                 scaleName = "Median Age",
                 states = "CA")