View source: R/panel.lmlineq.R
panel.lmlineq | R Documentation |
This is an extension of the panel functions panel.abline
and
panel.lmline
to also draw a label on the line. The
default label is the line equation, and optionally the R squared value
of its fit to the data points.
panel.ablineq(a = NULL, b = 0, h = NULL, v = NULL, reg = NULL, coef = NULL, pos = if (rotate) 1 else NULL, offset = 0.5, adj = NULL, at = 0.5, x, y, rotate = FALSE, srt = 0, label = NULL, varNames = alist(y = y, x = x), varStyle = "italic", fontfamily = "serif", digits = 3, r.squared = FALSE, sep = ", ", sep.end = "", col, col.text, col.line, ..., reference = FALSE) panel.lmlineq(x, y, ...)
a, b, h, v, reg, coef |
specification of the line.
The simplest usage is to give |
pos, offset |
passed on to |
adj |
passed on to |
fontfamily |
passed on to |
at |
position of the equation as a fractional distance along the line. This should be in the range 0 to 1. When a vertical line is drawn, this gives the vertical position of the equation. |
x, y |
position of the equation in native units. If given, this over-rides
|
rotate, srt |
set |
label |
the text to draw along with the line. If specified, this will be used instead of an equation. |
varNames |
names to display for |
varStyle |
the name of a |
digits |
number of decimal places to show for coefficients in equation. |
r.squared |
the R^2 statistic to display along with the equation of a line.
This can be given directly as a number, or |
sep, sep.end |
The R^2 ( |
..., col, col.text, col.line |
passed on to |
reference |
whether to draw the line in a "reference line" style, like that used for grid lines. |
The equation is constructed as an expression using plotmath
.
Felix Andrews felix@nfrac.org
panel.abline
,
panel.text
,
lm
,
plotmath
set.seed(0) xsim <- rnorm(50, mean = 3) ysim <- (0 + 2 * xsim) * (1 + rnorm(50, sd = 0.3)) ## basic use as a panel function xyplot(ysim ~ xsim, panel = function(x, y, ...) { panel.xyplot(x, y, ...) panel.ablineq(a = 0, b = 2, adj = c(0,1)) panel.lmlineq(x, y, adj = c(1,0), lty = 2, col.line = "grey", digits = 1) }) ## using layers: xyplot(ysim^2 ~ xsim) + layer(panel.ablineq(lm(y ~ x, subset = x <= 3), varNames = alist(y = y^2, x = x[x <= 3]), pos = 4)) ## rotated equation (depends on device aspect at plotting time) xyplot(ysim ~ xsim) + layer(panel.ablineq(lm(y ~ x), rotate = TRUE, at = 0.8)) ## horizontal and vertical lines xyplot(ysim ~ xsim) + layer(panel.ablineq(v = 3, pos = 4, at = 0.1, lty = 2, label = "3.0 (critical value)")) + layer(panel.ablineq(h = mean(ysim), pos = 3, at = 0.15, lty = 2, varNames = alist(y = plain(mean)(y)))) ## using layer styles, r.squared xyplot(ysim ~ xsim) + layer(panel.ablineq(lm(y ~ x), r.sq = TRUE, at = 0.4, adj=0:1), style = 1) + layer(panel.ablineq(lm(y ~ x + 0), r.sq = TRUE, at = 0.6, adj=0:1), style = 2) ## alternative placement of equations xyplot(ysim ~ xsim) + layer(panel.ablineq(lm(y ~ x), r.sq = TRUE, rot = TRUE, at = 0.8, pos = 3), style = 1) + layer(panel.ablineq(lm(y ~ x + 0), r.sq = TRUE, rot = TRUE, at = 0.8, pos = 1), style = 2) update(trellis.last.object(), auto.key = list(text = c("intercept", "no intercept"), points = FALSE, lines = TRUE))
Add the following code to your website.
For more information on customizing the embed code, read Embedding Snippets.