R help - Aug 2025 - ggplot with arrows

Consider:

x <- seq(-5,5,length.out = 100)
y <- x^2
data <- data.frame(x,y)
library(ggplot2)
ggplot(data,aes(x,y))+
? stat_function(
? ? fun = function(x) x^2,
? ? color = "blue", linewidth = 1.25
? ) +
? theme_linedraw()
I'd like to add an arrow to the ends of curve to illustrate the?curve
continues indefinitely in that direction,
ChatGPT suggests using geom_segment or geom_link but there has an easier way to
do this.

Any suggestions would be appreciated.


	[[alternative HTML version deleted]]

I would save the graph as a PowerPoint object and then edit it in PowerPoint.
library(ggplot2)
library(grid)
library(officer)
library(rvg)
x <- seq(-5, 5, length.out = 100)
y <- x^2
data <- data.frame(x, y)
plot <- ggplot(data, aes(x, y)) +
  geom_path(color = "blue", linewidth = 1.25) +
  geom_segment(
    aes(x = x[1], y = y[1], xend = x[100], yend = y[100]),
    arrow = arrow(angle = 20, type = "closed", ends =
"both", length = unit(0.2, "inches")),
    color = "red"
  ) +
  theme_linedraw()
doc <- read_pptx()
doc <- add_slide(doc, layout = "Title and Content", master =
"Office Theme")
doc <- ph_with(doc, dml(ggobj = plot), location = ph_location_fullsize())
print(doc, target = "quadratic_with_arrows.pptx")

If I remember I think you have to ungroup it in PowerPoint and then all elements
become editable. The general approach can be done with other file
formats/programs, not just PowerPoint.
Tim

-----Original Message-----
From: R-help <r-help-bounces at r-project.org> On Behalf Of Thomas Subia
via R-help
Sent: Friday, August 1, 2025 10:31 AM
To: r-help at r-project.org
Subject: [R] ggplot with arrows

[External Email]

Consider:

x <- seq(-5,5,length.out = 100)
y <- x^2
data <- data.frame(x,y)
library(ggplot2)
ggplot(data,aes(x,y))+
  stat_function(
    fun = function(x) x^2,
    color = "blue", linewidth = 1.25
  ) +
  theme_linedraw()
I'd like to add an arrow to the ends of curve to illustrate the curve
continues indefinitely in that direction, ChatGPT suggests using geom_segment or
geom_link but there has an easier way to do this.

Any suggestions would be appreciated.


        [[alternative HTML version deleted]]

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