Extracting information for our default/provided plot2d()

Extracting information for our default/provided plot2d()

extract_2d(zargs)

Arguments

zargs

The argument list as passed from zenplot(). This must at least contain x, vars, num, lim and labs (for extract_2d()); see zenplot() for an explanation of these variables.

Value

A list list with

x and y:

the data to be plotted in the 2d plot

xcols:

a list with all columns of x

groups:

the group numbers for each column of x

vars:

the variable numbers for each column of x

glabs:

the group labels for each column of x

vlabs:

the variable labels for each column of x

xlim and ylim:

the x-axis and y-axis limits, and

same.group:

a logical indicating whether the x and y variables belong to the same group.

Details

This is an auxiliary function called on zargs within any 1d plotting function (e.g. hist_1d_grid, density_1d_graphics, or points_1d_loon) to extract the 1d data from zargs needed for plotting. For performance reasons, no checking of the input object is done.

Note

Performance critical

See also

Other tools for constructing your own plot1d and plot2d functions: burst_aux(), burst(), check_zargs(), extract_1d(), plot_indices()

Other data extraction functions to build plots: extract_1d()

Other default 2d plot functions: arrow_2d_graphics(), arrow_2d_grid(), arrow_2d_loon(), axes_2d_graphics(), axes_2d_grid(), axes_2d_loon(), density_2d_graphics(), density_2d_grid(), density_2d_loon(), group_2d_graphics(), group_2d_grid(), group_2d_loon(), label_2d_graphics(), label_2d_grid(), label_2d_loon(), points_2d_graphics(), points_2d_grid(), points_2d_loon(), qq_2d_graphics(), qq_2d_grid(), rect_2d_graphics(), rect_2d_grid(), rect_2d_loon()

Author

Marius Hofert and Wayne Oldford

Examples

## This function is used within the default (any user defined)
## 2d plot functions
##
my_2d_plot <- function(zargs, your_name = "BillyBob", ...) {
                   data_2d <- extract_2d(zargs)
                   msg <- paste("Components of zargs available",
                                "to construct a 2d plot for ",
                                your_name)
                   print(msg)
                   ## just print the names of the data components
                   ## which you might want to use in your plot
                   print(names(data_2d))

                   ## You can plot whatever you want using the information in
                   ## could use any of these to construct any 1d plot you want
                   ## using R's graphics or any of zemplot's built in 1d plots.
                   ##
                   ## For example, here we could use
                   ## use zenplot's base graphics functions
                   ## First a scatterplot
                   points_2d_graphics(zargs, ...)
                   ## to which we overlay density contours
                   density_2d_graphics(zargs, add = TRUE, col = "steelblue", ...)
                   ## similar functions could be called for the other packages.
                   ## You can print the source of anyone of the default functions
                   ## to get some idea of managing details.
                }

## And now try it out
zenplot(iris, plot2d = my_2d_plot)
#> [1] "Components of zargs available to construct a 2d plot for  BillyBob"
#>  [1] "x"          "y"          "xcols"      "groups"     "vars"      
#>  [6] "glabs"      "vlabs"      "xlim"       "ylim"       "same.group"
#> [1] "Components of zargs available to construct a 2d plot for  BillyBob"
#>  [1] "x"          "y"          "xcols"      "groups"     "vars"      
#>  [6] "glabs"      "vlabs"      "xlim"       "ylim"       "same.group"
#> [1] "Components of zargs available to construct a 2d plot for  BillyBob"
#>  [1] "x"          "y"          "xcols"      "groups"     "vars"      
#>  [6] "glabs"      "vlabs"      "xlim"       "ylim"       "same.group"
#> [1] "Components of zargs available to construct a 2d plot for  BillyBob"
#>  [1] "x"          "y"          "xcols"      "groups"     "vars"      
#>  [6] "glabs"      "vlabs"      "xlim"       "ylim"       "same.group"