plotrix (version 3.0-2)

intersectDiagram: Display set intersections

Description

Display set intersections as rows of rectangles.

Usage

intersectDiagram(x,pct=FALSE,show.nulls=FALSE,xnames=NULL,namesep="-",
  mar=c(0,0,3,0),main="Intersection Diagram",cex=1,col=NULL,minspacing=0.1)

Arguments

x

A list containing as many numeric vectors as there are sets. The first vector contains the counts or percentages of the elements that are only in one set, the next vector contains the counts or percentages of elements that are in two sets and so on

pct

Whether to display counts (FALSE) or percentages (TRUE) of the number of entities.

show.nulls

Whether to display the number of original objects that were not members of any set.

xnames

Optional user supplied names for the set categories (see Details).

namesep

The separator to use between category names.

mar

The margins for the diagram. The margins that were in effect when the function is called are restored.

main

The title for the diagram.

col

Colors for the sets (see Details).

cex

Character expansion for the intersection labels.

minspacing

The minimum spacing between the rectangles as a proportion.

Value

• nil

Details

intersectDiagram displays rows of optionally colored rectangles. The topmost row represents the elements that only belong to one set, the next row down represents elements belonging to two sets, and so on to the bottom row of one rectangle representing the elements that belong to all the sets. More than three intersecting sets generally produce a complex and difficult to interpret Venn diagram, and this provides an alternative way to display the intersections between larger numbers of sets. Each set is assigned a color if col is not NA. rainbow is called if col is NULL, otherwise the colors passed are used. For each intersection, the colors representing the sets intersecting are included in the rectangle. The strings displayed on each rectangle are taken from the argument xnames unless that is NULL, then the names of the first element of the intersectList object passed as x or returned from the call to makeIntersectList and if this is also NULL, capital letters are assigned to each category in x. If there were objects in the original data set that were not members of any set, any percentages calculated will reflect this. By setting show.nulls to TRUE, the counts or percentages of such objects will be displayed below the intersections over an empty rectangle scaled to the count or percentage. If a matrix of set membership indicators is passed as x, it will be passed to makeIntersectList for conversion.

See Also

makeIntersectList, getIntersectList

Examples

# create a matrix where each row represents an element and
 # a 1 (or TRUE) in each column indicates that the element is a member
 # of that set.
 druguse<-matrix(c(sample(c(0,1),200,TRUE),
  sample(c(0,1),200,TRUE),
  sample(c(0,1),200,TRUE),
  sample(c(0,1),200,TRUE)),ncol=4)
 colnames(druguse)<-c("Alc","Tob","THC","Amp")
 druglist<-makeIntersectList(druguse)
 # first display it as counts
 intersectDiagram(druglist)
 # then as percent with non.members, passing the initial matrix
 intersectDiagram(druguse,pct=TRUE,show.nulls=TRUE)
 # alter the data to have more multiple intersections
 druguse[which(as.logical(druguse[,1]))[1:40],2]<-1
 druguse[which(as.logical(druguse[,1]))[31:70],3]<-1
 druguse[,4]<-sample(c(0,1),200,TRUE,prob=c(0.9,0.1))
 intersectDiagram(druguse,col=c("gray20","gray40","gray60","gray80"))