axis.default {lattice} | R Documentation |
Lattice funtions provide control over how the plot axes are annotated
through a common interface. There are two levels of control. The
xscale.components
and yscale.components
arguments can be
functions that determine tick mark locations and labels given a
packet. For more direct control, the axis
argument can be a
function that actually draws the axes. The functions documented here
are the defaults for these arguments. They can additonally be used as
components of user written replacements.
xscale.components.default(lim, packet.number = 0, packet.list = NULL, top = TRUE, ...) yscale.components.default(lim, packet.number = 0, packet.list = NULL, right = TRUE, ...) axis.default(side = c("top", "bottom", "left", "right"), scales, components, as.table, labels = c("default", "yes", "no"), ticks = c("default", "yes", "no"), ...)
lim |
the range of the data in that packet (data subset corresponding to a combination of levels of the conditioning variable). The range is not necessarily numeric; e.g. for factors, they could be character vectors representing levels, and for the various date-time representations, they could be vectors of length 2 with the corresponding class. |
packet.number |
which packet (counted according to the packet
order, described in print.trellis ) is being
processed. In cases where all panels have the same limits, this
function is called only once (rather than once for each packet), in
which case this argument will have the value 0 .
|
packet.list |
list, as long as the number of packets, giving all the actual packets. Specifically, each component is the list of arguments given to the panel function when and if that packet is drawn in a panel. (This has not yet been implemented.) |
top, right |
the value of the top and right
components of the result, as appropriate. See below for
interpretation. |
side |
on which side the axis is to be drawn. The usual partial matching rules apply. |
scales |
the appropriate component of the scales argument
supplied to the high level function, suitably standardized. |
components |
list, similar to those produced by
xscale.components.default and
yscale.components.default . |
as.table |
the as.table argument in the high level
function. |
labels |
whether labels are to be drawn. By default, the rules
determined by scales are used. |
ticks |
whether labels are to be drawn. By default, the rules
determined by scales are used. |
... |
many other arguments may be supplied, and are passed on to other internal functions. |
These functions are part of a new API introduced in lattice 0.14 to provide the user more control over how axis annotation is done. While the API has been designed in anticipation of use that was previously unsupported, the implementation has initially focused on reproducing existing capabilities, rather then test new features. At the time of writing, several features are unimplemented. If you require them, please contact the maintainer.
xscale.components.default
and yscale.components.default
return a list of the form suitable as the components
argument
of axis.default
. Valid components in the return value of
xscale.components.default
are:
|
A numeric limit for the box. |
|
A list with two elements, ticks and
labels . ticks must be a list with components
at and tck which give the location and lengths of tick
marks. tck can be a vector, and will be recycled to be as
long as at . labels must be a list with components
at , labels , and check.overlap . at and
labels give the location and labels of the tick labels; this
is usually the same as the location of the ticks, but is not
required to be so. check.overlap is a logical flag
indicating whether overlapping of labels should be avoided by
omitting some of the labels while rendering. |
|
This can be a logical flag; if TRUE ,
top is treated as being the same as bottom ; if
FALSE , axis annotation for the top axis is omitted.
Alternatively, top can be a list like bottom .
|
Valid components in the return value of
yscale.components.default
are left
and right
.
Their interpretations are analogous to (respectively) the
bottom
and top
components described above.
Deepayan Sarkar Deepayan.Sarkar@R-project.org
Lattice
,
xyplot
,
print.trellis
str(xscale.components.default(c(0, 1))) set.seed(36872) rln <- rlnorm(100) densityplot(rln, scales = list(x = list(log = 2), alternating = 3), xlab = "Simulated lognormal variates", xscale.components = function(...) { ans <- xscale.components.default(...) ans$top <- ans$bottom ans$bottom$labels$labels <- parse(text = ans$bottom$labels$labels) ans$top$labels$labels <- if (require(MASS)) fractions(2^(ans$top$labels$at)) else 2^(ans$top$labels$at) ans }) ## Direct use of axis to show two temperature scales (Celcius and ## Fahrenheit). This does not work for multi-row plots, and doesn't ## do automatic allocation of space F2C <- function(f) 5 * (f - 32) / 9 C2F <- function(c) 32 + 9 * c / 5 axis.CF <- function(side, ...) { ylim <- current.panel.limits()$ylim switch(side, left = { prettyF <- pretty(ylim) labF <- parse(text = sprintf("%s ~ degree * F", prettyF)) panel.axis(side = side, outside = TRUE, at = prettyF, labels = labF) }, right = { prettyC <- pretty(F2C(ylim)) labC <- parse(text = sprintf("%s ~ degree * C", prettyC)) panel.axis(side = side, outside = TRUE, at = C2F(prettyC), labels = labC) }, axis.default(side = side, ...)) } xyplot(nhtemp ~ time(nhtemp), aspect = "xy", type = "o", scales = list(y = list(alternating = 3)), axis = axis.CF, xlab = "Year", ylab = "Temperature", main = "Yearly temperature in New Haven, CT") ## version using yscale.components yscale.components.CF <- function(...) { ans <- yscale.components.default(...) ans$right <- ans$left ans$left$labels$labels <- parse(text = sprintf("%s ~ degree * F", ans$left$labels$at)) prettyC <- pretty(F2C(ans$num.limit)) ans$right$ticks$at <- C2F(prettyC) ans$right$labels$at <- C2F(prettyC) ans$right$labels$labels <- parse(text = sprintf("%s ~ degree * C", prettyC)) ans } xyplot(nhtemp ~ time(nhtemp), aspect = "xy", type = "o", scales = list(y = list(alternating = 3)), yscale.components = yscale.components.CF, xlab = "Year", ylab = "Temperature", main = "Yearly temperature in New Haven, CT")