mosaic (version 0.13.0)

freqpolygon: Frequency Polygons

Description

Frequency polygons are an alternative to histograms that make it simpler to overlay multiple distributions.

Usage

freqpolygon(x, ..., panel = "panel.freqpolygon",
  prepanel = "prepanel.default.freqpolygon")
prepanel.default.freqpolygon(x, darg = list(), plot.points = FALSE,
  ref = FALSE, groups = NULL, subscripts = TRUE, jitter.amount = 0.01 *
  diff(current.panel.limits()$ylim), center = NULL, nint = NULL,
  breaks = NULL, width = darg$width, type = "density", ...)
panel.freqpolygon(x, darg = list(), plot.points = FALSE, ref = FALSE,
  groups = NULL, weights = NULL, jitter.amount = 0.01 *
  diff(current.panel.limits()$ylim), type = "density", breaks = NULL,
  nint = NULL, center = NULL, width = darg$width,
  gcol = trellis.par.get("reference.line")$col,
  glwd = trellis.par.get("reference.line")$lwd, h, v, ...,
  identifier = "freqpoly")

Arguments

x

a formula or a numeric vector

panel

a panel function

prepanel

a prepanel function

darg

a list of arguments for the function computing the frequency polygon. This exists primarily for compatibility with densityplot and is unlikely to be needed by the end user.

plot.points

one of TRUE, FALSE, "jitter", or "rug" indicating how points are to be displayed

ref

a logical indicating whether a horizontal reference line should be added (roughly equivalent to h=0)

groups, weights, jitter.amount, identifier

as in densityplot or histogram

subscripts

as in other lattice prepanel functions

center

center of one of the bins

nint

an approximate number of bins for the frequency polygon

breaks

a vector of breaks for the frequency polygon bins

width

width of the bins

type

one of 'density', 'percent', or 'count'

gcol

color of guidelines

glwd

width of guidelines

h, v

a vector of values for additional horizontal and vertical lines

...

additional arguments passed on to histogram and panel.

Value

• a trellis object

Examples

freqpolygon(~age | substance, data=HELPrct, v=35)
freqpolygon(~age, data=HELPrct, labels=TRUE, type='count')
freqpolygon(~age | substance, data=HELPrct, groups=sex)
freqpolygon(~age | substance, data=HELPrct, groups=sex, ylim=c(0,0.11))
## comparison of histogram and frequency polygon
histogram(~eruptions, faithful, type='density', width=.5)
ladd( panel.freqpolygon(faithful$eruptions, width=.5 ))