makeIntersectList {plotrix} | R Documentation |
Create a list of set intersections from a matrix of indicators.
makeIntersectList(x,xnames=NULL)
x |
A data frame or matrix where rows represent objects and columns attributes. A 1 or TRUE indicates that the object (row) has that attribute or is a member of that set (column). |
xnames |
Optional user-supplied names for the categories of x. |
makeIntersectList reads a matrix (or data frame) containing only dichotomous values (either 0/1 or FALSE/TRUE). Each row represents an object and each column represents a set. A value of 1 or TRUE indicates that that object is a member of that set. The function creates a list of vectors that correspond to all combinations of the sets (set intersections) and inserts the counts of elements in each combination. If a row of the matrix is all zeros, it will not be counted, but the last element of the list returned contains the count of rows in x and thus non-members can be calculated.
makeIntersectList combines the set or attribute names to form intersection names. For the intersection of sets A and B, the name will be AB and so on. These are the names that will be displayed by intersectDiagram. To change these, use the xnames argument.
A list of the intersection counts or percentages and the total number of objects.
Jim Lemon
# 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. setdf<-data.frame(A=sample(c(0,1),100,TRUE,prob=c(0.7,0.3)), B=sample(c(0,1),100,TRUE,prob=c(0.7,0.3)), C=sample(c(0,1),100,TRUE,prob=c(0.7,0.3)), D=sample(c(0,1),100,TRUE,prob=c(0.7,0.3))) setdflist<-makeIntersectList(setdf) setdflist