Ladder Plot

Makes a ladder plot, similar to parcoord but with more flexibility and graphical options.

ladderplot(x, ...)
# Default S3 method
ladderplot(x, scale=FALSE, col=1, pch=19, lty=1, 
xlim=c(0.5, ncol(x) + 0.5), ylim=range(x), vertical = TRUE, ordered=FALSE,...)

Arguments

x

A matrix or data frame with at least 2 columns.

scale

Logical, if the original data columns should be scaled to the unit (0-1) interval.

col

Color values to use for rows of x. If longer than 1, its value is recycled.

pch

Point type to use. If longer than 1, its value is recycled.

lty

Line type to use. If longer than 1, its value is recycled.

xlim, ylim

Limits for axes.

vertical

Logical, if the orientation of the ladderplot should be vertical or horizontal.

ordered

Logical, if the columns in x should be ordered.

...

Other arguments passed to the function stripchart.

Details

The function uses stripchart to plot 1-D scatter plots for each column in x. Then points are joined by lines for each rows of x.

Value

Makes a plot as a side effect. Returns NULL invisibly.

Author

Peter Solymos <solymos@ualberta.ca>

See also

lines, points, stripchart

Almost identical function: parcoord

Examples

x<-data.frame(A=c(1:10), B=c(2:11)+rnorm(10))
y<-data.frame(x, C=c(1:10)+rnorm(10))
opar <- par(mfrow=c(1,3))
ladderplot(x)
ladderplot(x, col=1:10, vertical=FALSE)
ladderplot(y, col=1:10)

par(opar)

## examples from parcoord
if (FALSE) { # \dontrun{
if (require(MASS)) {
opar <- par(mfrow=c(2,3))
z1 <- state.x77[, c(7, 4, 6, 2, 5, 3)]
parcoord(z1, main="parcoord state.x77")
ladderplot(z1, pch=NA, scale=TRUE, main="ladderplot state.x77 original")
ladderplot(z1, main="ladderplot state.x77 original")
ir <- rbind(iris3[,,1], iris3[,,2], iris3[,,3])
z2 <- log(ir)[, c(3, 4, 2, 1)]
parcoord(z2, col = 1 + (0:149))
ladderplot(z2, scale=TRUE, col = 1 + (0:149),
    main="ladderplot iris original")
ladderplot(z2, col = 1 + (0:149))
par(opar)
}
} # }