stripchart {graphics} | R Documentation

## 1-D Scatter Plots

### Description

`stripchart` produces one dimensional scatter plots (or dot plots) of the given data. These plots are a good alternative to `boxplot`s when sample sizes are small.

### Usage

    stripchart(x, method = "overplot", jitter = 0.1, offset = 1/3,
               vertical = FALSE, group.names, add = FALSE,
               at = NULL, xlim = NULL, ylim = NULL,
               main = "", ylab = "", xlab = "",
               log = "", pch = 0, col = par("fg"), cex = par("cex"))

### Arguments

`x` | the data from which the plots are to be produced. The data can be specified as a single vector, or as list of vectors, each corresponding to a component plot. Alternatively a symbolic specification of the form `x ~ g` can be given, indicating the the observations in the vector `x` are to be grouped according to the levels of the factor `g`. `NA`s are allowed in the data.
`method` | the method to be used to separate coincident points. The default method `"overplot"` causes such points to be overplotted, but it is also possible to specify `"jitter"` to jitter the points, or `"stack"` have coincident points stacked. The last method only makes sense for very granular data.
`jitter` | when `method="jitter"` is used, `jitter` gives the amount of jittering applied.
`offset` | when stacking is used, points are stacked this many line-heights (symbol widths) apart.
`vertical` | when vertical is `TRUE` the plots are drawn vertically rather than the default horizontal.
`group.names` | group labels which will be printed alongside (or underneath) each plot.
`add` | logical, if true add the chart to the current plot.
`at` | numeric vector giving the locations where the charts should be drawn, particularly when `add = TRUE`; defaults to `1:n` where `n` is the number of boxes.
`xlim, ylim, main, ylab, xlab, log, pch, col, cex` | Graphical parameters.

### Details

Extensive examples of the use of this kind of plot can be found in Box, Hunter and Hunter or Seber and Wild.

### Examples

    x <- rnorm(50)
    xr <- round(x, 1)
    stripchart(x) ; m <- mean(par("usr")[1:2])
    text(m, 1.04, "stripchart(x, \"overplot\")")
    stripchart(xr, method = "stack", add = TRUE, at = 1.2)
    text(m, 1.35, "stripchart(round(x,1), \"stack\")")
    stripchart(xr, method = "jitter", add = TRUE, at = 0.7)
    text(m, 0.85, "stripchart(round(x,1), \"jitter\")")

    with(OrchardSprays,
         stripchart(decrease ~ treatment,
                    main = "stripchart(Orchardsprays)", ylab = "decrease",
                    vertical = TRUE, log = "y"))

    with(OrchardSprays,
         stripchart(decrease ~ treatment, at = c(1:8)^2,
                    main = "stripchart(Orchardsprays)", ylab = "decrease",
                    vertical = TRUE, log = "y"))

[Package graphics version 2.1.1 Index]