symmetry_plot: symmetry_plot

In deandevl/RplotterPkg: R Plotting Functions Using 'ggplot2'

symmetry_plot

Description

Function creates a ggplot2 based symmetry plot from a vector of numeric values.

Function orders the numeric vector from low to high. It then divides the data into two groups: values above the median(u group) and values below the median(v group). The distances from the median for values in each group are computed. A scatter plot is created where distances in the v group are plotted along the x axis and distances from the v group are plotted along the y axis. If the upper and lower distance data forms a straight line then the original data is perfectly symmetrical.

A reference symmetry line is also drawn. If points fall close to the line then the data is nearly symmetric. If the data is left-skewed, then the points fall below the line. If the data is right skewed, the points fall above the line.

Function returns a ggplot2 plot object of x/y scatter point distances from the median. Options are provided for axis scaling and point labeling.

Usage

symmetry_plot(
  df,
  var_name,
  position = position_jitter(width = 0, height = 0),
  title = NULL,
  subtitle = NULL,
  caption = NULL,
  center_titles = FALSE,
  x_title = "V",
  y_title = "U",
  hide_x_tics = FALSE,
  hide_y_tics = FALSE,
  rot_x_tic_angle = 0,
  rot_y_tic_label = FALSE,
  x_limits = NULL,
  x_major_breaks = waiver(),
  x_minor_breaks = waiver(),
  x_labels = waiver(),
  y_limits = NULL,
  y_major_breaks = waiver(),
  y_minor_breaks = waiver(),
  y_labels = waiver(),
  x_y_decimals = NULL,
  x_y_scientific = NULL,
  axis_text_size = 11,
  pts_fill = "black",
  pts_shape = 21,
  pts_stroke = 1,
  pts_color = "black",
  pts_size = 1,
  pts_alpha = 1,
  line_width = 0.6,
  line_color = "blue",
  line_alpha = 0.7,
  line_linetype = "solid",
  show_major_grids = TRUE,
  show_minor_grids = TRUE,
  panel_color = "white",
  panel_border_color = "black"
)

Arguments

df	The target data frame from which the distance from the median are plotted.
var_name	A string that sets the variable name of interest from 'df'. This is a required parameter.
position	A string or function that does a slight adjustment to overlapping points. Typical values are "jitter" or position_jitter(width = 0.1, height = 0.1).
title	A string that sets the plot title.
subtitle	A string that sets the plot subtitle.
caption	A string that sets the plot caption
center_titles	A logical which if TRUE centers both the 'title' and 'subtitle'.
x_title	A string that sets the x axis title. If NULL (the default) then the x axis title does not appear.
y_title	A string that sets the y axis title. If NULL (the default) then the y axis title does not appear.
hide_x_tics	A logical that controls the appearance of the x axis tics.
hide_y_tics	A logical that controls the appearance of the y axis tics.
rot_x_tic_angle	A numeric that sets the angle of rotation for the x tic labels. When x tic labels are long, a value of 40 for this argument usually works well.
rot_y_tic_label	A logical which if TRUE rotates the y tic labels 90 degrees for enhanced readability.
x_limits	Sets the minimum and maximum for the x axis.
x_major_breaks	A numeric vector or function that defines the exact major tic locations along the x axis.
x_minor_breaks	A numeric vector or function that defines the exact minor tic locations along the x axis.
x_labels	A character vector with the same length as 'x_major_breaks', that labels the major tics.
y_limits	A numeric 2 element vector that sets the minimum and maximum for the y axis.
y_major_breaks	A numeric vector or function that defines the exact major tic locations along the y axis.
y_minor_breaks	A numeric vector or function that defines the exact minor tic locations along the y axis.
y_labels	A character vector with the same length as 'y_major_breaks', that labels the major tics.
x_y_decimals	A two element numeric vector that set the number of decimals for the x and y tic labels.
x_y_scientific	A two element logical vector that if TRUE uses scientific notation for the x and y tic labels.
axis_text_size	A numeric that sets the font size along the axis'. Default is 11.
pts_fill	A string that sets the fill color attribute of the points.
pts_shape	A numeric integer that sets the shape attribute of the points. Typical values are 21 "circle", 22 "square", 23 "diamond", 24 "up triangle", 25 "down triangle".
pts_stroke	A numeric that sets the drawing stroke width attribute for a point shape.
pts_color	A string that sets the color attribute of the points.
pts_size	A numeric value that sets the size attribute of the points.
pts_alpha	A numeric value that sets the alpha level attribute of points.
line_width	A numeric value that sets the width of the symmetry line.
line_color	A string that sets the color of the symmetry line.
line_alpha	A numeric that sets the alpha of the symmetry line.
line_linetype	A string that sets the symmetry line type "twodash", "solid", "longdash", "dotted", "dotdash", "dashed", "blank".
show_major_grids	A logical that controls the appearance of major grids.
show_minor_grids	A logical that controls the appearance of minor grids.
panel_color	A string in hexidecimal or color name that sets the plot panel's color. The default is "white".
panel_border_color	A string in hexidecimal or color name that sets the plot panel's border color. The default is "black".

Value

A ggplot class plot object

Examples

library(ggplot2)
library(RplotterPkg)

RplotterPkg::symmetry_plot(
  df = RplotterPkg::farms,
  var_name = "count",
  title = "Symmetry in farm counts across US states",
  rot_y_tic_label = TRUE,
  line_linetype = "dotted"
)

deandevl/RplotterPkg documentation built on March 1, 2025, 11:17 a.m.