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
xis 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.defaultsuch asinclude.lowest,rightandlabels.- 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, thecountscomponent of the result; ifFALSE, 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)
# NOT RUN {
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")
# }