image
or
persp
.
The user may supply an explicit list of breakpoints,
or a suggested number of classes.
hist2d(x, y, xbreaks=<<see below>>, ybreaks=<<see below>>, nxbins=<<see below>>, nybins=<<see below>>, scale=F)
x
can give both dimensions by being a list with
x
and
y
components, or a matrix with two columns
(the first column is
x
, the second column is
y
).
Missing values are not allowed.
x
data,
nxbin
is ignored if
xbreaks
is supplied.
y
data,
nybin
is ignored if
ybreaks
is supplied.
TRUE
,
z
is scaled so that the volume under the histogram is
1
.
If
FALSE
,
z
contains the actual counts.
x
bins.
y
bins.
x
, and the number of
columns is the length of the output
y
.
x
y
Missing values are not counted.
hist2d
calculates the counts for a 2-dimensional histogram.
These counts may be used in
persp
,
image
,
contour
or some other
plotting routine.
The default number of bins is computed by a variant of Doane's rule
and breakpoints are chosen so that few datapoints lie on a breakpoint.
corn <- list(x = corn.rain, y = corn.yield) image(hist2d(corn, nxbins=9, ny=9)) points(corn, col=0) prim <- hist2d(prim9[,3:4], nxbin=30, nybin=30) persp(prim$z/max(prim$z), eye=c(-6, -4, 3))