This help topic is for R version 1.5.0. For the current version of R, try https://stat.ethz.ch/R-manual/R-patched/library/base/html/hist.POSIXt.html
hist.POSIXt {base}R Documentation

Histogram of a Date-Time Object

Description

Method for hist applied to date-time objects.

Usage

## S3 method for class 'POSIXt'
hist(x, breaks, ..., plot = TRUE, freq = FALSE,
     start.on.monday = TRUE, format)

Arguments

x

an object inheriting from class "POSIXt".

breaks

a vector of cut points or number giving the number of intervals which x is to be cut into or an interval specification, one of "secs", "mins", "hours", "days", "weeks", "months" or "years".

...

graphical parameters.

plot

logical. If TRUE (default), a histogram is plotted, otherwise a list of breaks and counts is returned.

freq

logical; if TRUE, the histogram graphic is a representation of frequencies, i.e, the counts component of the result; if FALSE, relative frequencies (“probabilities”) are plotted.

start.on.monday

logical. If breaks = "weeks", should the week start on Mondays or Sundays?

format

for the x-axis labels. See strptime.

Value

An object of class "histogram": see hist.

See Also

seq.POSIXt, axis.POSIXct, hist

Examples

hist(.leap.seconds, "years", freq = TRUE)
hist(.leap.seconds,
     seq(ISOdate(1970, 1, 10), ISOdate(2002, 1, 1), "5 years"))

## 100 random dates in a 10-week period
random.dates <- ISOdate(2001, 1, 1) + 70*86400*runif(100)
hist(random.dates, "weeks", format = "%d %b")
[Package base version 1.5.0 ]