xyplot.R
### Copyright 2001 Deepayan Sarkar <deepayan@stat.wisc.edu>
###
### This file is part of the lattice library for R.
### It is made available under the terms of the GNU General Public
### License, version 2, or at your option, any later version,
### incorporated herein by reference.
###
### This program is distributed in the hope that it will be
### useful, but WITHOUT ANY WARRANTY; without even the implied
### warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
### PURPOSE. See the GNU General Public License for more
### details.
###
### You should have received a copy of the GNU General Public
### License along with this program; if not, write to the Free
### Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
### MA 02111-1307, USA
prepanel.default.xyplot <-
function(x, y, type, ...)
{
## Note: shingles satisfy is.numeric()
if (length(x) && length(x)) {
ord <- order(x)
list(xlim = if (is.numeric(x)) range(x[is.finite(x)]) else levels(x),
ylim = if (is.numeric(y)) range(y[is.finite(y)]) else levels(y),
dx = as.numeric(diff(x[ord])),
dy = as.numeric(diff(y[ord])))
}
else list(c(NA, NA),
c(NA, NA),
1, 1)
}
panel.xyplot <-
function(x, y, type="p",
pch = plot.symbol$pch,
col,
col.line = plot.line$col,
col.symbol = plot.symbol$col,
lty = plot.line$lty,
cex = plot.symbol$cex,
lwd = plot.line$lwd, ...)
{
x <- as.numeric(x)
y <- as.numeric(y)
if (length(x)>0) {
if (!missing(col)) {
if (missing(col.line)) col.line <- col
if (missing(col.symbol)) col.symbol <- col
}
plot.symbol <- trellis.par.get("plot.symbol")
plot.line <- trellis.par.get("plot.line")
if ("o" %in% type || "b" %in% type)
type <- c(type, "p", "l")
if ("p" %in% type)
lpoints(x = x, y = y, cex = cex,
col = col.symbol, pch=pch)
if ("l" %in% type)
llines(x=x, y=y, lty=lty, col=col.line, lwd=lwd)
if ("h" %in% type)
llines(x=x, y=y, type = "h", lty=lty, col=col.line, lwd=lwd)
if ("s" %in% type) {
ord <- order(x)
n <- length(x)
xx <- numeric(2*n-1)
yy <- numeric(2*n-1)
xx[2*1:n-1] <- x[ord]
yy[2*1:n-1] <- y[ord]
xx[2*1:(n-1)] <- x[ord][-1]
yy[2*1:(n-1)] <- y[ord][-n]
llines(x=xx, y=yy,
lty=lty, col=col.line, lwd=lwd)
}
if ("S" %in% type) {
ord <- order(x)
n <- length(x)
xx <- numeric(2*n-1)
yy <- numeric(2*n-1)
xx[2*1:n-1] <- x[ord]
yy[2*1:n-1] <- y[ord]
xx[2*1:(n-1)] <- x[ord][-n]
yy[2*1:(n-1)] <- y[ord][-1]
llines(x=xx, y=yy,
lty=lty, col=col.line, lwd=lwd)
}
if ("r" %in% type) {
panel.lmline(x, y, col = col.line, lty = lty, lwd = lwd, ...)
}
if ("smooth" %in% type) {
panel.loess(x, y, col = col.line, lty = lty, lwd = lwd, ...)
}
}
}
xyplot <-
function(formula,
data = parent.frame(),
aspect = "fill",
layout = NULL,
panel = if (is.null(groups)) "panel.xyplot"
else "panel.superpose",
prepanel = NULL,
scales = list(),
strip = TRUE,
groups = NULL,
xlab,
xlim,
ylab,
ylim,
...,
panel.groups = "panel.xyplot",
subscripts = !is.null(groups),
subset = TRUE)
{
##dots <- eval(substitute(list(...)), data, parent.frame())
dots <- list(...)
groups <- eval(substitute(groups), data, parent.frame())
if (!is.function(panel)) panel <- eval(panel)
if (!is.function(strip)) strip <- eval(strip)
prepanel <-
if (is.function(prepanel)) prepanel
else if (is.character(prepanel)) get(prepanel)
else eval(prepanel)
## Step 1: Evaluate x, y, etc. and do some preprocessing
form <- latticeParseFormula(formula, data)
cond <- form$condition
number.of.cond <- length(cond)
y <- form$left
x <- form$right
if (number.of.cond == 0) {
strip <- FALSE
cond <- list(as.factor(rep(1, length(x))))
layout <- c(1,1,1)
number.of.cond <- 1
}
subset <- eval(substitute(subset), data, parent.frame())
if ("subscripts" %in% names(formals(eval(panel)))) subscripts <- TRUE
if(subscripts) subscr <- seq(along=x)
x <- x[subset, drop = TRUE]
y <- y[subset, drop = TRUE]
if (subscripts) subscr <- subscr[subset, drop = TRUE]
if (missing(xlab)) xlab <- form$right.name
if (missing(ylab)) ylab <- form$left.name
## Convert both x and y to numeric: WHY ? (take c/o POSIXct)
if(!(is.numeric(x) && is.numeric(y)))
warning("Both x and y should be numeric")
##if (!(is.numeric(x))) x <- as.numeric(x)
##if (!(is.numeric(y))) y <- as.numeric(y)
## create a skeleton trellis object with the
## less complicated components:
foo <- do.call("trellis.skeleton",
c(list(aspect = aspect,
strip = strip,
panel = panel,
xlab = xlab,
ylab = ylab), dots))
dots <- foo$dots # arguments not processed by trellis.skeleton
foo <- foo$foo
foo$call <- match.call()
foo$fontsize.normal <- 10
foo$fontsize.small <- 8
## This is for cases like xlab/ylab = list(cex=2)
if (is.list(foo$xlab) && !is.characterOrExpression(foo$xlab$label))
foo$xlab$label <- form$right.name
if (is.list(foo$ylab) && !is.characterOrExpression(foo$ylab$label))
foo$ylab$label <- form$left.name
## Step 2: Compute scales.common (leaving out limits for now)
##scales <- eval(substitute(scales), data, parent.frame())
if (is.character(scales)) scales <- list(relation = scales)
foo <- c(foo,
do.call("construct.scales", scales))
## Step 3: Decide if limits were specified in call:
have.xlim <- !missing(xlim)
if (!is.null(foo$x.scales$limit)) {
have.xlim <- TRUE
xlim <- foo$x.scales$limit
}
have.ylim <- !missing(ylim)
if (!is.null(foo$y.scales$limit)) {
have.ylim <- TRUE
ylim <- foo$x.scales$limit
}
## Step 4: Decide if log scales are being used:
have.xlog <- !is.logical(foo$x.scales$log) || foo$x.scales$log
have.ylog <- !is.logical(foo$y.scales$log) || foo$y.scales$log
if (have.xlog) {
xlog <- foo$x.scales$log
xbase <-
if (is.logical(xlog)) 10
else if (is.numeric(xlog)) xlog
else if (xlog == "e") exp(1)
x <- log(x, xbase)
if (have.xlim) xlim <- log(xlim, xbase)
}
if (have.ylog) {
ylog <- foo$y.scales$log
ybase <-
if (is.logical(ylog)) 10
else if (is.numeric(ylog)) ylog
else if (ylog == "e") exp(1)
y <- log(y, ybase)
if (have.ylim) ylim <- log(ylim, ybase)
}
## Step 5: Process cond
cond <- lapply(cond, as.factorOrShingle, subset, drop = TRUE)
cond.max.level <- unlist(lapply(cond, nlevels))
id.na <- is.na(x)|is.na(y)
for (var in cond)
id.na <- id.na | is.na(var)
if (!any(!id.na)) stop("nothing to draw")
## Nothing simpler ?
foo$condlevels <- lapply(cond, levels)
## Step 6: Evaluate layout, panel.args.common and panel.args
foo$panel.args.common <- dots
if (subscripts) foo$panel.args.common$groups <- groups
layout <- compute.layout(layout, cond.max.level, skip = foo$skip)
plots.per.page <- max(layout[1] * layout[2], layout[2])
number.of.pages <- layout[3]
foo$skip <- rep(foo$skip, length = plots.per.page)
foo$layout <- layout
nplots <- plots.per.page * number.of.pages
foo$panel.args <- as.list(1:nplots)
cond.current.level <- rep(1,number.of.cond)
panel.number <- 1 # this is a counter for panel number
for (page.number in 1:number.of.pages)
if (!any(cond.max.level-cond.current.level<0))
for (plot in 1:plots.per.page) {
if (foo$skip[plot]) foo$panel.args[[panel.number]] <- FALSE
else if(!any(cond.max.level-cond.current.level<0)) {
id <- !id.na
for(i in 1:number.of.cond)
{
var <- cond[[i]]
id <- id &
if (is.shingle(var))
((var >= levels(var)[[cond.current.level[i]]][1])
& (var <= levels(var)[[cond.current.level[i]]][2]))
else (as.numeric(var) == cond.current.level[i])
}
foo$panel.args[[panel.number]] <-
list(x = x[id], y = y[id])
if (subscripts)
foo$panel.args[[panel.number]]$subscripts <-
subscr[id]
cond.current.level <-
cupdate(cond.current.level,
cond.max.level)
}
panel.number <- panel.number + 1
}
foo <- c(foo,
limits.and.aspect(prepanel.default.xyplot,
prepanel = prepanel,
have.xlim = have.xlim, xlim = xlim,
have.ylim = have.ylim, ylim = ylim,
x.relation = foo$x.scales$relation,
y.relation = foo$y.scales$relation,
panel.args.common = foo$panel.args.common,
panel.args = foo$panel.args,
aspect = aspect,
nplots = nplots))
class(foo) <- "trellis"
foo
}
