plot_map: Create a choropleth map from census data.

In censusindia: Census of India Data, 1901-2011, with Boundaries and Projections

Create a choropleth map from census data.

Description

Create a choropleth map from census data.

Usage

plot_map(
  data,
  fill_var,
  title = NULL,
  subtitle = NULL,
  legend_title = NULL,
  palette = "viridis",
  reverse = FALSE,
  direction = NULL,
  na_color = "grey80",
  boundary_year = NULL,
  base_layer = TRUE,
  show_state_boundaries = FALSE,
  state_boundary_color = "black",
  state_boundary_width = 0.3,
  trans = "identity",
  midpoint = NULL,
  oob = NULL,
  limits = NULL,
  breaks = NULL,
  labels = NULL,
  font_family = NULL,
  legend_position = "right"
)

Arguments

data	An sf object or data frame with geometry attached via attach_geometry
fill_var	The variable to map to fill color (unquoted or string)
title	Optional title for the map
subtitle	Optional subtitle for the map
legend_title	Title for the legend
palette	Color palette. Options include: "viridis" - Perceptually uniform, colorblind-friendly (default) "red_blue" - Diverging red to blue (red = high) "blue_red" - Diverging blue to red (blue = high) "greens" - Sequential green palette "oranges" - Sequential orange palette "reds" - Sequential red palette "blues" - Sequential blue palette "purple_green" - Diverging purple to green
reverse	Logical. Reverse the color palette direction? Default FALSE.
direction	Numeric. Alternative to reverse: use -1 to reverse, 1 for default. If both reverse and direction are specified, direction takes precedence.
na_color	Color for missing values. Default is "grey80"
boundary_year	Census year whose state boundaries to draw beneath the data, keeping India's full claimed extent on the map even where the census enumerates no districts. Defaults to the year column if present.
base_layer	Logical. Draw India's full state outline beneath the data? Default TRUE
show_state_boundaries	Logical. Overlay state boundaries?
state_boundary_color	Color for state boundaries. Default is "black"
state_boundary_width	Width of state boundary lines. Default is 0.3
trans	Transformation for the color scale (e.g., "log10", "sqrt"). Default is "identity" (no transformation)
midpoint	Value to centre a diverging palette on, e.g. 0 for growth or 1000 for a sex ratio. Without it the palette centres on the middle of limits, which is rarely the meaningful value.
oob	How to treat values outside limits. The ggplot2 default censors them to na_color, making them indistinguishable from genuinely missing data; pass scales::squish to clamp them to the nearest end instead.
limits	Optional limits for the color scale as c(min, max)
breaks	Optional breaks for the legend
labels	Optional labels for the legend breaks
font_family	Font family for all map text. Default NULL uses the system default; e.g. "Arial".
legend_position	One of "right" (default), "left", "bottom", "top", or "none". "bottom"/"top" also turns the colorbar horizontal.

Value

A ggplot2 object

Examples

# Calculate ST percentage and attach geometry
st_data <- census_2011_pca |>
  dplyr::mutate(st_pct = 100 * st_population / population_total) |>
  attach_geometry(2011)

# Create a basic map
plot_map(st_data, st_pct, title = "ST Population %")

# With red-blue palette and state boundaries
plot_map(st_data, st_pct,
  title = "ST Population % (2011)",
  palette = "red_blue",
  show_state_boundaries = TRUE
)

censusindia documentation built on Oct. 15, 2026, 5:08 p.m.