Multi-Panel Scatterplot Matrices

DESCRIPTION:

Create a Trellis multi-panel scatterplot matrix plot. A modified version of the plot is created if the data argument is a bigdata bdFrame (see the DETAILS).

USAGE:

splom(formula, data = sys.parent(1), panel = panel.splom, xlim = c(0,1), 
      ylim = c(0,1), aspect = 1, between = list(x = 0.5, y = 0.5), 
      scales = list(axs = "i", draw = F), superpanel = panel.pairs,  
      ..., subset = subset, xbins=30, col.regions, maxcount)) 
The following arguments have special meaning within this function. The common meanings for these and all other arguments are listed separately under trellis.args.

ARGUMENTS:

formula
a formula of the form: ~ x | g1 * g2 * ... however the given variables g1, g2 , ... may be omitted. The x variable is a numeric matrix or a data frame with p columns. Factor variables in a data frame are converted to numeric variables. Variables on the right hand side of the vertical bar are factors or shingles, and are used to parcel out the x observations (rows) to various panels. Each panel is a p-by- p scatterplot matrix, composed of subpanels.

If data is a bdFrame the formula specification is more like the modeling functions:
~ . means plot all columns.
~ . - xVar means plot all columns except xVar.
~ . | groupVar means make a panel for each level of groupVar.
~ . - xVar + log(xVar) means plot all columns except xVar but include log of xVar.

aspect
aspect ratio of each panel (and subpanel), square by default.
between
to avoid confusion between panels and subpanels, the default is to show the panels of a splom plot with space between them.
panel
function that is used to plot the data on each subpanel of a splom display.
superpanel
function that sets up the splom display, by default as a scatterplot matrix.
xbins
the size of the hexbin grid. Only used if data is a bdFrame.
col.regions
the colors used for the hexbins. Only used if data is a bdFrame.
maxcount
a numeric value, map this value to the last color. This may be useful to make several splom plots have the same mapping of count to color. Only used if data is a bdFrame.

VALUE:

an object of class trellis, which is automatically plotted by print.trellis.
Unlike the function pairs, there are no axis labels on a splom plot.

DETAILS:

If the data argument is a bdFrame then a hexbin plots are drawn in each panel instead of scatterplot. A color key is drawn at the side to show the color - count mapping. As noted above, the formula specification for a bigdata splom plot is different from the formula used in the traditional splom plot.

SEE ALSO:

.

EXAMPLES:

new.iris <- as.data.frame.array(iris, col.dims = 2) 
splom( ~ new.iris[, 1:4] | new.iris[, 6], layout = c(3, 1),  
      main = "Iris Data") 
splom( ~ state.x77 | state.region, layout = c(2,2))