cpcp {extracat}R Documentation

Parallel Coordinates Plot for categorical data

Description

This function provides a parallel coordinates plot for categorical as well as continuous data based on the ipcp function in the iplots package. It applies sorted numeric point sequences to the categories which indicate the relative frequencies and allow a sensible interactive highlighting. There are options to change the rule for the gaps between these sequences and to apply an additional ordering algorithm.

Usage

cpcp(V, ord = NULL, freqvar = NULL, numerics = NULL, gap.type = "equal.tot",
        na.rule = "omit", spread = 0.3, gap.space = 0.2, psp = FALSE, 
        scr.res = c(1280, 1024), sort.individual = FALSE, jitter = FALSE)

Arguments

V data frame containing the variables for the plot. A special choice and order can be made by setting the second argument ord.If V is a frequency table (see e.g. ftable) the frequency variable has to be named "Freq".
freqvar Optional name of a frequency variable in V. If V contains a variable called "Freq" (see ftable) it will be defined as frequency variable if freqvar is unspecified.
numerics An integer vector specifying the indices of numeric variables. Variables of class "numeric" are indicated automatically but integer variables are not.
ord An integer vector specifying the indices and order of the variables.
gap.type The rule for the gaps between different categories: "equal.gaps" will lead to equal gap sizes in the whole plot (and thus depends on the maximum number of categories). "equal.tot" will force the gaps within each variable to sum up to gap.space. "spread" will lead to equal distances between the centerpoints of each category. In the latter case the spread value denotes the maximal spread width around each centerpoint.
na.rule "omit" will omit all incomplete cases from V. Otherwise all NAs will be transformed to categories called "n/a".
spread The maximum width of a single category if gap.type is set to "spread". Should lie between 0 and 1.
gap.space The space parameter for each gap. Should lie in [0,1).
psp If TRUE parallel spineplots will be drawn below the plot.
scr.res The screen resolution used for the plot size.
sort.individual If TRUE all polygones with the same categories in two neighboring variables will be drawn together in the right variable.
jitter logical: whether or not to jitter integer variables which are treated as a numeric variable.

Value

No return value.

Author(s)

Alexander Pilhoefer
Department for Computer Oriented Statistics and Data Analysis
University of Augsburg
Germany

References

Alexander Pilhoefer New approaches in visualization of categorical data: R-package extracat
Journal of Statistical Software, submitted Jan 2010

See Also

ipcp listen resort

Examples

cpcp(V = housing)

[Package extracat version 1.0-0 Index]