hist {base} | R Documentation |
The generic function hist
computes and plots (if plot=T
) a
histogram of the given data values.
hist(x, ...) hist.default(x, breaks, freq = NULL, probability = !freq, include.lowest = TRUE, right = TRUE, col = NULL, border = par("fg"), main = paste("Histogram of", deparse(substitute(x))), xlim = range(breaks), ylim = range(counts, 0), xlab = deparse(substitute(x)), ylab, axes = TRUE, plot = TRUE, labels = FALSE, nclass = NULL, ...)
x |
a vector of values for which the histogram is desired. |
breaks |
either a single number giving the approximate number of cells for the histogram or a vector giving the breakpoints between histogram cells. |
freq |
logical; if TRUE , the
histogram graphic is to present a representation of frequencies, i.e,
the counts component of the result; if FALSE ,
relative frequencies (``probabilities''), the rel.freqs ,
are plotted. Defaults to TRUE iff breaks are
equidistant. |
probability |
an alias for !freq , for S compatibility. |
include.lowest |
logical; if TRUE ,
an `x[i]' equal to the `breaks' value will be included in the first
(or last, for right = FALSE ) bar. |
right |
logical; if TRUE , the histograms cells are
right-closed (left open) intervals. |
col |
a colour to be used to fill the bars.
The default of NULL yields unfilled bars. |
border |
the color of the border around the bars. |
main, xlab, ylab |
these arguments to title have useful
defaults here. |
xlim, ylim |
the range of x and y values with sensible defaults. |
plot |
logical. If TRUE (default), a histogram is
plotted, otherwise a list of breaks and counts is returned. |
labels |
logical. Additionally draw labels on top of bars,
if TRUE . |
nclass |
numeric (integer). For S compatibility only,
nclass=n is equivalent to breaks=n (n scalar). |
... |
further graphical parameters to title and axis . |
If right = TRUE
(default), the histogram cells are intervals
of the form (a,b]
, i.e. they include their right-hand endpoint,
but not their left one, with the exception of the first cell when
include.lowest
is TRUE
.
For right = FALSE
, the intervals are of the form [a,b)
,
and include.lowest
really has the meaning of
``include highest''.
breaks |
the n+1 cell boundaries (= breaks if that
was a vector). |
counts |
n integers; for each cell, the number of
x[] inside. |
intensities |
values f^(x[i]), as estimated
density values. If all(diff(breaks) == 1) , they are the
relative frequencies counts/n and in general satisfy
sum[i; f^(x[i])
(b[i+1]-b[i])] = 1, where b[i] = breaks[i] . |
mids |
the n cell midpoints; useful for plotting. |
The resulting value does not depend on the values of
the arguments freq
(or probability
)
or plot
. This is intentionally different from S.
data(islands) op <- par(mfrow=c(2,2)) hist(islands) str(hist(islands, col="gray", labels = TRUE)) hist(sqrt(islands), br = 12, col="lightblue", border="pink") ##-- For non-equidistant breaks, counts should NOT be graphed unscaled: r <- hist(sqrt(islands), br = c(4* 0:5,10* 3:5,70,100,140), col='blue1') text(r$mids, r$intensities, r$counts, adj=c(.5,-.5), col='blue3') sapply(r[2:3],sum) sum(r$intensities * diff(r$breaks)) # == 1 par(op) str(hist(islands, plot= F)) str(hist(islands, br=12, plot= F)) str(hist(islands, br=c(12,20,36,80,200,1000,17000), plot = F)) str(hist(islands, br=c(12,20,36,80,200,1000,17000), freq = TRUE))#warning