plotrix (version 3.8-2)

weighted.hist: Display a weighted histogram

Description

Calculate the counts of the weighted values in specified bins and optionally display either a frequency or density histogram.

Usage

weighted.hist(x,w,breaks="Sturges",col=NULL,plot=TRUE,
 freq=TRUE,ylim=NA,ylab=NULL,xaxis=TRUE,...)

Value

A list containing:

breaks - The endpoints of the intervals

counts - The weighted counts

density - The weighted counts divided by their sum.

mids - The midpoints of the intervals and the bars displayed.

xname - the name of x.

Arguments

x

A vector of numeric values

w

A vector of weights at least as long as x.

breaks

The endpoints of the ranges into which to count the weighted values.

col

An optional vector of colors for the bars of the histogram.

plot

Whether to plot a histogram.

freq

Whether to plot counts or densities.

ylim

The limits of the plot ordinate.

ylab

Label for the ordinate.

xaxis

Whether to display an X axis.

...

additional arguments passed to barplot.

Author

Jim Lemon and Hadley Wickham - thanks to Ben Graf for asking for a custom x axis option and Martin Maechler for fixing the barplot problem

Details

weighted.hist calculates the weighted counts of values falling into the ranges specified by breaks. Instead of counting each value as 1, it counts the corresponding value in w (the weight).

breaks may be specified by a monotonically increasing vector of numbers that are interpreted as the endpoints of the ranges, a single number representing the number of ranges desired or the name of the function to calculate the ranges (see hist). If a vector of numbers is passed that does not include all values in x, the user is warned.

See Also

hist

Examples

 testx<-sample(1:10,300,TRUE)
 testw<-seq(1,4,by=0.01)
 weighted.hist(testx,testw,breaks=1:10,main="Test weighted histogram")