xhistogram: Augmented histograms

In mosaic: Project MOSAIC Statistics and Mathematics Teaching Utilities

Augmented histograms

Description

The mosaic package adds some additional functionality to lattice::histogram(), making it simpler to obtain certain common histogram adornments. This is done be resetting the default panel and prepanel functions used by histogram.

Usage

xhistogramBreaks(x, center = NULL, width = NULL, nint, ...)

prepanel.xhistogram(x, breaks = xhistogramBreaks, ...)

panel.xhistogram(
  x,
  dcol = trellis.par.get("plot.line")$col,
  dalpha = 1,
  dlwd = 2,
  gcol = trellis.par.get("add.line")$col,
  glwd = 2,
  fcol = trellis.par.get("superpose.polygon")$col,
  dmath = dnorm,
  verbose = FALSE,
  dn = 100,
  args = NULL,
  labels = FALSE,
  density = NULL,
  under = FALSE,
  fit = NULL,
  start = NULL,
  type = "density",
  v,
  h,
  groups = NULL,
  center = NULL,
  width = NULL,
  breaks,
  nint = round(1.5 * log2(length(x)) + 1),
  stripes = c("vertical", "horizontal", "none"),
  alpha = 1,
  ...
)

Arguments

x	a formula or a numeric vector
center	center of one of the bins
width	width of the bins
nint	approximate number of bins
...	additional arguments passed from lattice::histogram() to the panel function; by default when the mosaic package has been loaded this will be panel.xhistogram().
breaks	break points for histogram bins, a function for computing such, or a method hist() knows about given as a character string. When using the mosaic package defaults, xhistogramBreaks() is used.
dcol	color of density curve
dalpha	alpha for density curve
dlwd, glwd	like lwd but affecting the density line and guide lines, respectively
gcol	color of guidelines
fcol	fill colors for histogram rectangles when using groups. (Use col, which is passed through to the histogram panel function, when not using groups.)
dmath	density function for density curve overlay
verbose	be verbose?
dn	number of points to sample from density curve
args	a list of additional arguments for dmath
labels	should counts/densities/percents be displayed or each bin?
density	a logical indicating whether to overlay a density curve
under	a logical indicating whether the density layers should be under or over other layers of the plot.
fit	a character string describing the distribution to fit. Known distributions include "exponential", "normal", "lognormal" , "poisson", "beta", "geometric", "t", "weibull", "cauchy", "gamma", "chisq", and "chi-squared"
start	numeric value passed to MASS::fitdistr()
type	one of 'density', 'count', or 'percent'
h, v	a vector of values for additional horizontal and vertical lines
groups	as per lattice::histogram()
stripes	one of "vertical", "horizontal", or "none", indicating how bins should be striped when groups is not NULL
alpha	transparency level
panel	a panel function

Details

The primary additional functionality added to histogram() are the arguments width and center which provide a simple way of describing equal-sized bins, and fit which can be used to overlay the density curve for one of several distributions. The groups argument can be used to color the bins. The primary use for this is to shade tails of histograms, but there may be other uses as well.

Value

xhistogramBreaks returns a vector of break points

Note

Versions of lattice since 0.20-21 support setting custom defaults for breaks, panel, and prepanel used by histogram(), so xhistogram() is no longer needed. As a result, xhistogram() (which was required in earlier versions of mosaic is no longer needed and has been removed.

See Also

lattice::histogram(), mosaicLatticeOptions(), and restoreLatticeOptions().

Examples

if (require(mosaicData)) {
histogram(~age | substance, HELPrct, v=35, fit='normal')
histogram(~age, HELPrct, labels=TRUE, type='count')
histogram(~age, HELPrct, groups=cut(age, seq(10,80,by=10)))
histogram(~age, HELPrct, groups=sex, stripes='horizontal')
histogram(~racegrp, HELPrct, groups=substance,auto.key=TRUE)
xhistogramBreaks(1:10, center=5, width=1)
xhistogramBreaks(1:10, center=5, width=2)
xhistogramBreaks(0:10, center=15, width=3)
xhistogramBreaks(1:100, center=50, width=3)
xhistogramBreaks(0:10, center=5, nint=5)
}

mosaic documentation built on May 29, 2024, 5:27 a.m.