# hist.POSIXt

##### Histogram of a Date or Date-Time Object

Method for `hist`

applied to date or date-time objects.

##### Usage

```
# S3 method for POSIXt
hist(x, breaks, …,
xlab = deparse(substitute(x)),
plot = TRUE, freq = FALSE,
start.on.monday = TRUE, format, right = TRUE)
```# S3 method for Date
hist(x, breaks, …,
xlab = deparse(substitute(x)),
plot = TRUE, freq = FALSE,
start.on.monday = TRUE, format, right = TRUE)

##### Arguments

- x
an object inheriting from class

`"POSIXt"`

or`"Date"`

.- 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`"days"`

,`"weeks"`

,`"months"`

,`"quarters"`

or`"years"`

, plus`"secs"`

,`"mins"`

,`"hours"`

for date-time objects.- …
graphical parameters, or arguments to

`hist.default`

such as`include.lowest`

,`right`

and`labels`

.- xlab
a character string giving the label for the x axis, if plotted.

- 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`

.- right
logical; if

`TRUE`

, the histogram cells are right-closed (left open) intervals.

##### Details

Note that unlike the default method, `breaks`

is a required argument.

Using `breaks = "quarters"`

will create intervals of 3 calendar
months, with the intervals beginning on January 1, April 1,
July 1 or October 1, based upon `min(x)`

as appropriate.

With the default `right = TRUE`

, breaks will be set
on the last day of the previous period when `breaks`

is
`"months"`

, `"quarters"`

or `"years"`

. Use
`right = FALSE`

to set them to the first day of the
interval shown in each bar.

##### Value

An object of class `"histogram"`

: see `hist`

.

##### See Also

##### Examples

`library(graphics)`

```
hist(.leap.seconds, "years", freq = TRUE)
hist(.leap.seconds,
seq(ISOdate(1970, 1, 1), ISOdate(2020, 1, 1), "5 years"))
rug(.leap.seconds, lwd=2)
## 100 random dates in a 10-week period
random.dates <- as.Date("2001/1/1") + 70*stats::runif(100)
hist(random.dates, "weeks", format = "%d %b")
```

*Documentation reproduced from package graphics, version 3.4.0, License: Part of R 3.4.0*