gline: Line chart

In R4VN: Health Data Analysis and Publication-Ready Reporting

Line chart

Description

Draws an ordered trend for one numeric outcome, optionally with separate lines by group.

Usage

gline(
  data = NULL, x, y = NULL, vars = NULL, by = NULL,
  stat = c("identity", "mean", "median"), points = TRUE, line_width = 2,
  line_type = 1, sort = TRUE, pch = 16, point_size = 0.9, xlab = NULL,
  ylab = NULL, xtitle = NULL, ytitle = NULL, xbreaks = NULL, ybreaks = NULL,
  title = NULL, subtitle = NULL, note = NULL, color = NULL,
  palette = "default", alpha = 1, legend = TRUE, legend_position = "topright",
  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.
y	Optional numeric variable. When omitted, bars show counts or percentages. When supplied, bars show a mean or median.
vars	Optional vars(...) selector used to request several variables in one call.
by	Optional grouping variable or hierarchical vars(...) specification.
stat	"identity", "mean", or "median". Mean or median collapses repeated x values within each group.
points	Show points along each line.
line_width, line_type	Width and line type of connecting lines.
sort	Sort observations by x within each line.
pch	Point symbol.
point_size	Point-size multiplier.
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, ybreaks	Numeric tick positions used with xlab and 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.
legend	Show the legend when by is supplied.
legend_position	Base-R legend position, for example "topright" or "topleft".
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.

Details

Draws one x variable against one or several y variables with optional hierarchical grouping.

Value

An object of class r4vn_graph; its data component contains the plotted or aggregated values.

Examples

d <- data.frame(
  year = rep(2022:2024, 2),
  rate = c(12, 15, 18, 10, 13, 17),
  sex = rep(c("Male", "Female"), each = 3)
)
gline(d, x = year, y = rate)
gline(d, x = year, y = rate, by = sex, points = TRUE)

# Extended usage examples

d <- data.frame(year = rep(2022:2024, 2),
                rate = c(12, 15, 18, 10, 13, 17),
                sex = rep(c("Male", "Female"), each = 3))
gline(d, x = year, y = rate, show = FALSE)
gline(d, x = year, y = rate, by = sex, points = TRUE, show = FALSE)

# Collapse repeated x values to means or medians
d2 <- rbind(d, transform(d, rate = rate + 2))
gline(d2, x = year, y = rate, by = sex, stat = "mean", show = FALSE)

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