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 as "facets".

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

stateMap(
  data = NULL,
  parameter = NULL,
  state_SFDF = "USCensusStates_02",
  breaks = NULL,
  palette = "brewer.blues",
  conusOnly = TRUE,
  stateCode = NULL,
  projection = NULL,
  stateBorderColor = "gray50",
  title = NULL,
  showLegend = TRUE,
  legendTitle = NULL,
  legendOrientation = "portrait",
  legendPosition = 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.
breaks: Numeric vector of break points.
palette: A vector of colors or palette name from the cols4all package (see cols4all::c4a).
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: Named projection, e.g. "EPSG:4326" or "WGS84" or proj4string.
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'.
showLegend: Logical specifying whether or not to show the legend.
legendTitle: Text string to use as the legend title.
legendOrientation: Orientation of the legend. Either "portrait" or "landscape".
legendPosition: A tm_pos object generated with tmap::tm_pos_in() or tmap::tm_pos_out().

Value

A ggplot object.

Examples

library(MazamaSpatialPlots)

stateMap(
  data = example_US_stateObesity,
  parameter = "obesityRate",
  stateBorderColor = "white",
  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,
    bg.color = "grey85",
    inner.margins  = .05
  ) +
  tmap::tm_title(
    text = 'Obesity Rate by State',
    size = 1.5,
    position = tmap::tm_pos_in("center", "top"),
    fontfamily = "serif"
  )


# Example using stateCode
stateMap(
  data = example_US_stateObesity,
  parameter = "obesityRate",
  stateCode = c('ME', 'NH', 'VT', 'MA', 'RI', 'CT'),
  stateBorderColor = 'black',
  legendPosition = tmap::tm_pos_in("right", "bottom")
) +
  tmap::tm_layout(
    frame = TRUE,
    frame.double.line = TRUE,
    bg.color = "grey85",
    inner.margins  = .08
  ) +
  tmap::tm_title(
    text = 'Obesity Rates in New England',
    size = 1.5,
    fontface = 2,
    fontfamily = "serif",
    position = tmap::tm_pos_in("center", "top")
  )