gstars: Grid-Based 'stars' Function
In gsymbols: Grid-based symbols

Description Usage Arguments Details Author(s) See Also Examples

Similar to stars function, but drawn in grid viewport: Draw star plots or segment diagrams of a multivariate data set. With one single location, also draws 'spider' (or 'radar') plots.

gstars(x, radius = TRUE, locations = "grid", 
       draw.segments = FALSE, scale = TRUE, full = TRUE, 
       qx = apply(x, 2, quantile, probs = seq(0, 1, 0.1)), 
       quantile=FALSE, col.segments=TRUE, col.stars=FALSE, 
       draw.labels=TRUE, key=FALSE, lwd=0.3, lty=1, cex=1)

`x`	vector, matrix or data frame of data. One star or segment plot will be produced for each row of `x`. Missing values (`NA`) are allowed, but they are treated as if they were 0 (after scaling, if relevant).
`radius`	logical flag: in `TRUE`, the radii corresponding to each variable in the data will be drawn.
`locations`	Either two column matrix with the x and y coordinates used to place each of the segment plots; or numeric of length 2 when all plots should be superimposed (for a `spider plot`). By default, `locations = NULL`, the segment plots will be placed in a rectangular grid.
`draw.segments`	logical. If `TRUE` draws a segment diagram.
`scale`	logical flag: if `TRUE`, the columns of the data matrix are scaled independently so that the maximum value in each column is 1 and the minimum is 0. If `FALSE`, the presumption is that the data have been scaled by some other algorithm to the range [0,1]. If `x` is a vector scale is forced `TRUE`.
`full`	logical flag: if `TRUE`, the segment plots will occupy a full circle. Otherwise, they occupy the (upper) semicircle only.
`qx`	matrix or data frame of data for quantiles in background
`quantile`	logical. If `TRUE`, draws quantiles in background.
`col.segments`	colour vector (integer or character, see `par`), each specifying a colour for one of the segments (variables). If `FALSE` no colour is used. If `TRUE` vector of length `col(x)` is used. Ignored if `draw.segments = FALSE`.
`col.stars`	colour vector (integer or character, see `par`), each specifying a colour for one of the stars (cases). If `FALSE` no colour is used. If `TRUE` vector of length `col(x)` is used. Ignored if `draw.segments = TRUE`.
`draw.labels`	logical. If `TRUE` draws labels.
`key`	logical. If `TRUE` draws only labels (e.g. caption)
`lwd`	line width, passed to `gp` for Grid functions
`lty`	line type, passed to `gp` for Grid functions
`cex`	numerical value, giving the amount by which plotting text and symbols should be magnified relative to the default, passed to `gp` for Grid functions

Missing values are treated as 0.

Each star plot or segment diagram represents one row of the input x. Variables (columns) start on the right and wind counter-clockwise around the circle. The size of the (scaled) column is shown by the distance from the center to the point on the star or the radius of the segment representing the variable.

Only one page of output is produced.

Ingo Voglhuber

gbarplot, gmatplot, gpie, gsymbols, gbxp

data(USJudgeRatings)
grid.newpage()

## example

gstars(USJudgeRatings)

grid.newpage()

## no radii
gstars(USJudgeRatings,radius=FALSE)

grid.newpage()

## no labels
gstars(USJudgeRatings, draw.labels=FALSE)

grid.newpage()

## segments of a circle
gstars(USJudgeRatings,draw.segments=TRUE)

grid.newpage()

## spiderplot, no labels
gstars(USJudgeRatings,radius=FALSE, locations="spider", 
           draw.labels=FALSE)

grid.newpage()

## spiderplot with quantiles in background
gstars(USJudgeRatings,radius=FALSE, locations="spider", 
           quantile=TRUE)

grid.newpage()

## spiderplot with quantiles in background
gstars(USJudgeRatings,radius=FALSE, locations="spider",
  qx=apply(USJudgeRatings,2,quantile,probs=seq(0,1,0.25)) , 
           quantile=TRUE,
  draw.labels=FALSE)

grid.newpage()

## draw only labels
gstars(USJudgeRatings, key=TRUE)