histStack: Histogram "stacked" by categories

In plotrix: Various Plotting Functions

Histogram "stacked" by categories

Description

Histogram of a quantitative variable with bars that are "stacked" by the values of a factor variable.

Usage

 histStack(x,...)

 ## S3 method for class 'formula'
histStack(x,data,breaks="Sturges",col="rainbow",
  right=TRUE,main="",xlab=NULL,legend.pos=NULL,cex.legend=0.75,...)

 ## Default S3 method:
histStack(x,z,breaks="Sturges",col="rainbow",
  right=TRUE,main="",xlab=NULL,legend.pos=NULL,cex.legend=0.75,...)

Arguments

x	A vector of quantitative data or a formula of the form x~z (see z below).
z	A vector of categorical data (a factor) that will define the “stacks”.
data	A data frame that contains both x and z.
breaks	Breaks to use in categorizing values of x.
col	Either a vector of colors in any legitimate form or a character string that specifies a function that requires only the length of the vector as an argument and will return a vector of colors with that length. (see Details)
right	A logical that indicates whether the bins are right-open (left-closed; =TRUE) or right-closed (left-open; =FALSE; default).
main	A character string that forms the main title for the plot.
xlab	A character string for labeling the x-axis.
legend.pos	A character string or two numeric values indicating the position for the stacking legend.
cex.legend	A numeric character expansion value for the legend. Values less than 1 will make the legend smaller.
...	Additional arguments sent to the hist function.

Details

‘⁠histStack⁠’ displays a “stacked histogram” while using many of the same arguments as hist(). The argument ‘⁠z⁠’ will be converted to a factor with a warning if it is not already a factor.

The color functions in grDevices (e.g. "gray.colors") should always be valid when passed as the ‘⁠col⁠’ argument. Any function that will return a vector of ‘⁠n⁠’ colors when called with a single argument ‘⁠n⁠’ and that exists in the current environment should work. An error will occur if length(col)==1 and the value is not a function as described for ‘⁠col⁠’ (e.g., ‘⁠col="blue"⁠’ will result in an error).If fewer colors than levels of ‘⁠z⁠’ are passed, they will be recycled.

Value

nil. A plot is displayed.

Note

This function is currently experimental.

Author(s)

Derek Ogle with modifications by Jim Lemon

See Also

hist, legend

Examples

 set.seed(409)
 df<-data.frame(len=rnorm(100)+5,
  grp=sample(c("A","B","C","D"),100,replace=TRUE))
 histStack(len~grp,data=df,main="Default (rainbow) colors",
  xlab="Length category")
 histStack(len~grp,data=df,col="heat.colors",main="Heat colors",
  xlab="Length category",legend.pos="topright")
 histStack(len~grp,data=df,col=2:5,main="Colors by number",
  xlab="Length category",legend.pos=c(2.8,18))

plotrix documentation built on Nov. 10, 2023, 5:07 p.m.