State level thematic map — stateMap • MazamaSpatialPlots

Uses the tmap package to generate a thematic map at the state level. Input consists of a dataframe with stateCode identifiers.

Data to plot is specified with parameter argument. If parameter is mult-valued, mutliple plots will be generated and displayed in a "small multiples" matrix.

The returned object is a tmap ggplot object which can be further modified with ggplot options.

stateMap(
  data = NULL,
  parameter = NULL,
  state_SFDF = "USCensusStates_02",
  palette = "YlOrBr",
  breaks = NULL,
  conusOnly = TRUE,
  stateCode = NULL,
  projection = NULL,
  stateBorderColor = "gray50",
  title = NULL,
  main.title = NULL
)

Arguments

data: Dataframe containing values to plot. This dataframe must contain a column named stateCode with the 2-character state code.
parameter: Name of the column in data to use for coloring the map.
state_SFDF: simple features data frame with US states. It's data @slot must contain a column named stateCode with the 2-character state code.
palette: Palette name or a vector of colors based on RColorBrewer.
breaks: Numeric vector of break points.
conusOnly: Logical specifying Continental US state codes. Ignored when the stateCode argument is specified.
stateCode: Vector of state codes to include on the map.
projection: Specified method to represent surface of Earth.
stateBorderColor: Color used for state borders.
title: Vector of text strings to use as individual plot titles. This must be the same length as 'parameter'.
main.title: Text string to use as an overall title for all plots.

Value

A ggplot object.

Details

See tmap::tm_fill() for a more detailed description of the following parameters:

palette
breaks

Examples

library(MazamaSpatialPlots)

stateMap(
  data = example_US_stateObesity,
  parameter = "obesityRate",
  palette = "BuPu",
  stateBorderColor = "white",
  main.title = "2018 Obesity by State"
)


# Example of customization using tm_layout and breaks parameter
stateMap(
  data = example_US_stateObesity,
  parameter = "obesityRate",
  breaks = seq(20,38,3),
  stateBorderColor = 'black'
) +
  tmap::tm_layout(
    frame = TRUE,
    frame.double.line = TRUE,
    main.title = 'Obesity Rate by State',
    main.title.position = c("center", "top"),
    fontfamily = "serif",
    bg.color = "grey85",
    inner.margins  = .05
  )


# Example using stateCode
stateMap(
  data = example_US_stateObesity,
  parameter = "obesityRate",
  stateCode = c('ME', 'NH', 'VT', 'MA', 'RI', 'CT'),
  stateBorderColor = 'black',
  title = 'Obesity Rates in New England'
) +
  tmap::tm_layout(
    frame = TRUE,
    frame.double.line = TRUE,
    title.size = 1.2,
    title.fontface = 2,
    fontfamily = "serif",
    bg.color = "grey85",
    inner.margins  = .08
  )