ClevelandDotPlot {WVPlots}

Plot a Cleveland dot plot.

Description

Plot counts of a categorical variable.

Usage

ClevelandDotPlot(
  frm,
  xvar,
  title,
  ...,
  sort = -1,
  limit_n = NULL,
  stem = TRUE,
  color = "black"
)

Arguments

frm

data frame to get values from

xvar

name of the independent (input or model) column in frame

title

title to place on plot

...

no unnamed argument, added to force named binding of later arguments.

sort

if TRUE sort data

limit_n

if not NULL number of items to plot

stem

if TRUE add stems/whiskers to plot

color

color for points and stems

Details

Assumes that xvar is a factor or can be coerced to one (character or integral).

• sort < 0 sorts the factor levels in decreasing order (most frequent level first)

• sort > 0 sorts the factor levels in increasing order (good when used in conjunction with coord_flip())

• sort = 0 leaves the factor levels in "natural order" – usually alphabetical

• stem = FALSE will plot only the dots, without the stem to the y=0 line.

• limit_n = NULL plots all the levels, N an integer limits to the top N most populous levels

Examples

if (requireNamespace('data.table', quietly = TRUE)) {
	# don't multi-thread during CRAN checks
		data.table::setDTthreads(1)
}

set.seed(34903490)
# discrete variable: letters of the alphabet
# frequencies of letters in English
# source: http://en.algoritmy.net/article/40379/Letter-frequency-English
letterFreqs = c(8.167, 1.492, 2.782, 4.253, 12.702, 2.228,
                2.015, 6.094, 6.966, 0.153, 0.772, 4.025, 2.406, 6.749, 7.507, 1.929,
                0.095, 5.987, 6.327, 9.056, 2.758, 0.978, 2.360, 0.150, 1.974, 0.074)
letterFreqs = letterFreqs/100
letterFrame = data.frame(letter = letters, freq=letterFreqs)
# now let's generate letters according to their letter frequencies
N = 1000
randomDraws = data.frame(draw=1:N,
  letter=sample(letterFrame$letter, size=N,
  replace=TRUE, prob=letterFrame$freq))
WVPlots::ClevelandDotPlot(randomDraws, "letter",
  title = "Example Cleveland-style dot plot")

# # Note the use of sort = 0. Also note that the graph omits counts
# # with no occurrences (5, and 7)
# WVPlots::ClevelandDotPlot(mtcars, "carb", sort = 0, "Example of counting integer values")

# # For counting integer values while including counts with no occurrences,
# # use Discrete Distribution.
# WVPlots::DiscreteDistribution(mtcars, "carb", "Better way to count integer values")