stat_xspline: X-spline Statistic for ggplot2 (adapted from ggalt)

In TransProR: Analysis and Visualization of Multi-Omics Data

X-spline Statistic for ggplot2 (adapted from ggalt)

Description

This statistic adds an X-spline interpolation to your ggplot2 plots, allowing for smooth curves through a series of points. The implementation is adapted from the stat_xspline function in the ggalt package (GPL-3), originally authored by Bob Rudis.

Usage

stat_xspline(
  mapping = NULL,
  data = NULL,
  geom = "line",
  position = "identity",
  na.rm = TRUE,
  show.legend = NA,
  inherit.aes = TRUE,
  spline_shape = -0.25,
  open = TRUE,
  rep_ends = TRUE,
  ...
)

Arguments

mapping	Set of aesthetic mappings created by aes() or aes_().
data	The data to be displayed in this layer.
geom	The geometric object to use display the data.
position	Position adjustment, either as a string, or the result of a call to a position adjustment function.
na.rm	If FALSE (the default), removes missing values with a warning. If TRUE silently removes missing values.
show.legend	logical. Should this layer be included in the legends?
inherit.aes	If FALSE, overrides the default aesthetics, rather than combining with them.
spline_shape	Numeric value controlling the shape of the spline. Default is -0.25.
open	Logical. If TRUE, the spline is open; if FALSE, it is closed.
rep_ends	Logical. If TRUE, the end points are repeated.
...	Other arguments passed on to layer().

Value

A ggplot2 layer that can be added to a plot.

License and Attribution

This code is adapted from the ggalt package (https://github.com/hrbrmstr/ggalt), which is licensed under GPL-3. Original author: Bob Rudis ([e-mail]).

Computed variables

• x X coordinates of the spline.

• y Y coordinates of the spline.

Examples

library(ggplot2)
df <- data.frame(x = 1:10, y = cumsum(rnorm(10)))
ggplot(df, aes(x, y)) +
  geom_point() +
  stat_xspline(spline_shape = 0.5)

TransProR documentation built on Sept. 13, 2025, 1:09 a.m.