rgr (version 1.0.4)

gx.ecdf: Emprical Cumulative Distribution Function (ECDF)

Description

Displays an empirical cumulative distribution function (ECDF) plot with a zero-to-one linear y-scale as part of the multi-panel display provided by shape. The function may also be used stand-alone.

Usage

gx.ecdf(xx, xlab = deparse(substitute(xx)), 
	ylab = "Empirical Cumulative Distribution Function", 
	log = FALSE, xlim = NULL, main = " ", pch = 3, ifqs = FALSE)

Arguments

xx

name of the variable to be plotted.

xlab

a title for the x-axis. It is often desirable to replace the default x-axis title of the input variable name text string with a more informative title, e.g., xlab = "Cu (mg/kg) in <2 mm="" o-horizon="" soil"<="" code="">.

ylab

a title for the y-axis, defaults to "Emprical Cumulative Distribution Function".

log

if it is required to display the data with logarithmic (x-axis) scaling, set log = TRUE.

xlim

when used in the shape function, xlim is determined by gx.hist and used to ensure all four panels in shape

main

when used stand-alone a title may be added optionally above the plot by setting main, e.g., main = "Kola Project, 1995".

pch

by default the plotting symbol is set to a plus, pch = 3, alternate plotting symbols may be chosen from those displayed by display.marks.

ifqs

setting ifqs = TRUE results in horizontal and vertical dotted lines being plotted at the three central quartiles and their values, respectively.

See Also

display.marks, ltdl.fix.df, remove.na

Examples

## Make test data available
data(kola.o)
attach(kola.o)

## Plot a simple ECDF
gx.ecdf(Cu)

## Plot an ECDF with more appropriate labelling and with the quartiles
## indicated
gx.ecdf(Cu , xlab = "Cu (mg/kg) in <2 mm O-horizon soil", log = TRUE, 
ifqs = TRUE)   

## Detach test data
detach(kola.o)