3 way Venn Diagram in R

Dear Friends,
I had three list A, B and C having 700, 800 and 1200 elements in each and I wanted to draw a three way Venn diagram along with the list of elements in each part of diagram. The diagram mostly looks like in the figure.

The diagram shows three blocks A,B and C overlapping each other. The different overlapping areas are named with prefix "x". I programmed it in R to calculate the items list in xA,xB,xC,xAB.xBC,xAC,xABC and their counts. The program code is like this


# read the data from a text file (tab delimited) where column length may be different as a matrix (if column length is same you can read it is as dataframe)
a=read.table("test.txt",header=T,sep="\t")
a_mat=as.matrix(a)

# name the columns as A,B,C
A=a_mat[,1]
B=a_mat[,2]
C=a_mat[,3]

#Calculate the Venn diagram components using set theory rules of R
xA=setdiff(setdiff(A,B),C)
xB=setdiff(setdiff(B,C),A)
xC=setdiff(setdiff(C,B),A)
xAB=setdiff(intersect(A,B),C)
xBC=setdiff(intersect(B,C),A)
xAC=setdiff(intersect(A,C),B)
xABC=intersect(A,intersect(B,C))

# write the results in a text file .. (problem : the output is one column long list with seven headers, I didn't know how to create seven different columns at a time in this case, but it served my purpose)
write(c("\nxA",xA,"\nxB",xB,"\nxC",xC,"\nxAB",xAB,"\nxBC",xBC,"\nxAC",xAC,"\nxABC",xABC),file="result.txt");

# for quick testing the program you can define three list as
# define 3 sets
A=c(1,2,3,4,5,6,7,8)
B=c(3,4,5,6,7,8,9,10)
C=c(4,5,6,7,8,9,10,11,12,13)

# to count elements in each set say in xA, you can use length() function
LxA=length(xA) # calculate count of elements in list xA.

--------------ALL code at a complete program-----------------

A=c(1,2,3,4,5,6,7,8)
B=c(3,4,5,6,7,8,9,10)
C=c(4,5,6,7,8,9,10,11,12,13)
xA=setdiff(setdiff(A,B),C)
xB=setdiff(setdiff(B,C),A)
xC=setdiff(setdiff(C,B),A)
xAB=setdiff(intersect(A,B),C)
xBC=setdiff(intersect(B,C),A)
xAC=setdiff(intersect(A,C),B)
xABC=intersect(A,intersect(B,C))
write(c("\nxA",xA,"\nxB",xB,"\nxC",xC,"\nxAB",xAB,"\nxBC",xBC,"\nxAC",xAC,"\nxABC",xABC),file="result.txt");

----------------------code ends----------------------------------------


Online programs that can draw Venn diagrams but wouldn't worked in my cases.
1)http://bioinfogp.cnb.csic.es/tools/venny/index.html - It won't tell you the list of elements in each category
2) http://sablab.net/venn.php - Haven't checked the program
3)http://www.pangloss.com/seidel/Protocols/venn.cgi - Nice program but wont work with long list

Have fun...

I am a Bioinformatician at UMMC Medical Center Jackson MS