ghist: Histogram

In R4VN: Health Data Analysis and Publication-Ready Reporting

Histogram

Description

Draws histograms for one or several numeric variables using base R graphics. by may be a single grouping variable or hierarchical vars(...); histogram panels are created for observed group/stratum combinations.

Usage

ghist(
  data = NULL, x = NULL, vars = NULL, by = NULL, bins = "Sturges",
  density = FALSE, normal = FALSE, xlab = NULL, ylab = NULL, xtitle = NULL,
  ytitle = NULL, xbreaks = NULL, ybreaks = NULL, title = NULL,
  subtitle = NULL, note = NULL, color = NULL, palette = "default",
  alpha = 0.85, border_color = "white", normal_color = "black",
  normal_lty = 1, normal_lwd = 2, xline = NULL, yline = NULL,
  ref_color = "gray40", ref_lty = 2, ref_lwd = 1, theme = "journal",
  size = 11, combine = FALSE, ncol = NULL, file = NULL, width = 7, height = 5,
  dpi = 300, show = TRUE, bg = "white", vline = NULL, hline = NULL
)

Arguments

data	A data frame. It may be omitted when an active R4VN data frame exists.
x	Categorical variable on the horizontal axis. Supply an unquoted name or a character name.
vars	Optional vars(...) selector used to request several variables in one call.
by	Optional grouping variable or hierarchical vars(...) specification.
bins	Number of bins, a vector of break points, or a valid value for graphics::hist().
density	If TRUE, the vertical axis shows density rather than counts.
normal	Add a fitted normal density curve.
xlab	Optional category labels. Use an unnamed vector in displayed order or a named vector such as c(M = "Male", F = "Female").
ylab	Optional y-axis tick labels.
xtitle, ytitle	Axis titles. Variable names or variable labels are used automatically when possible.
xbreaks	Numeric x-axis tick positions used with xlab.
ybreaks	Numeric positions used with ylab.
title, subtitle, note	Main title, subtitle, and note.
color	A color name or vector of colors. When NULL, palette is used.
palette	One of "default", "journal", "blue", "green", "warm", "gray", or "colourblind"; alternatively, a color vector.
alpha	Color opacity from 0 to 1.
border_color	Histogram-bar border colour.
normal_color, normal_lty, normal_lwd	Colour, line type, and width of the optional normal-reference curve.
xline, yline	Optional numeric reference lines on the x and y axes. Thus xline draws vertical lines and yline draws horizontal lines.
ref_color, ref_lty, ref_lwd	Color, line type, and width for reference lines; vectors are recycled for multiple lines.
theme	Graph theme: "journal", "clean", "minimal", or "classic".
size	Base font size.
combine	When several graphs are produced, draw them as labelled panels in one figure.
ncol	Optional number of columns in a combined figure.
file	Optional output file ending in png, jpg, tiff, pdf, or svg.
width, height	Output width and height in inches.
dpi	Resolution for raster output.
show	Draw the graph in the current graphics device.
bg	Background color for exported files.
vline, hline	Deprecated aliases for xline and yline.

Value

An object of class r4vn_graph; its data component contains histogram breaks, counts, density, and midpoints.

Examples

d <- data.frame(age = c(18, 21, 25, 27, 31, 34, 38, 45, 51, 62))
ghist(d, x = age)
ghist(d, x = age, bins = 5, normal = TRUE, color = "steelblue")

d$sex <- rep(c("Female", "Male"), length.out = nrow(d))
ghist(d, x = age, by = sex, normal = TRUE, xline = 40, ref_lty = 2)
ghist(d, vars = vars(age), by = vars(sex), normal = TRUE, combine = TRUE)


# Extended usage examples

d <- data.frame(age = c(18, 21, 25, 27, 31, 34, 38, 45, 51, 62))
ghist(d, x = age, show = FALSE)
ghist(d, x = age, bins = 5, show = FALSE)
ghist(d, x = age, density = TRUE, normal = TRUE, show = FALSE)

R4VN documentation built on Sept. 30, 2026, 5:13 p.m.