R 为元素之间的关系构造对称矩阵

有一个矩阵：

infor <- cbind(c("1st","2nd","3rd","4th","5th","6th"), c("a;b;c","c;d;e;f","a;c;d","b;g;h","b;d;e","e;h"))
infor
     [,1]  [,2]     
[1,] "1st" "a;b;c"  
[2,] "2nd" "c;d;e;f"
[3,] "3rd" "a;c;d"  
[4,] "4th" "b;g;h"  
[5,] "5th" "b;d;e"  
[6,] "6th" "e;h" 

然后我建立了两个矩阵aa和bb：

> aa <- matrix(rep(infor[, 2], dim(infor)[1]), nrow=dim(infor)[1])
> aa
     [,1]      [,2]      [,3]      [,4]      [,5]      [,6]     
[1,] "a;b;c"   "a;b;c"   "a;b;c"   "a;b;c"   "a;b;c"   "a;b;c"  
[2,] "c;d;e;f" "c;d;e;f" "c;d;e;f" "c;d;e;f" "c;d;e;f" "c;d;e;f"
[3,] "a;c;d"   "a;c;d"   "a;c;d"   "a;c;d"   "a;c;d"   "a;c;d"  
[4,] "b;g;h"   "b;g;h"   "b;g;h"   "b;g;h"   "b;g;h"   "b;g;h"  
[5,] "b;d;e"   "b;d;e"   "b;d;e"   "b;d;e"   "b;d;e"   "b;d;e"  
[6,] "e;h"     "e;h"     "e;h"     "e;h"     "e;h"     "e;h"    
> bb <- t(aa)
> bb
     [,1]    [,2]      [,3]    [,4]    [,5]    [,6] 
[1,] "a;b;c" "c;d;e;f" "a;c;d" "b;g;h" "b;d;e" "e;h"
[2,] "a;b;c" "c;d;e;f" "a;c;d" "b;g;h" "b;d;e" "e;h"
[3,] "a;b;c" "c;d;e;f" "a;c;d" "b;g;h" "b;d;e" "e;h"
[4,] "a;b;c" "c;d;e;f" "a;c;d" "b;g;h" "b;d;e" "e;h"
[5,] "a;b;c" "c;d;e;f" "a;c;d" "b;g;h" "b;d;e" "e;h"
[6,] "a;b;c" "c;d;e;f" "a;c;d" "b;g;h" "b;d;e" "e;h"

> Overlaps <- function(a, b){
    spliteA <- strsplit(a, ";")
    spliteB <- strsplit(b, ";")
    score <- length(intersect(spliteA, spliteB))
    return(score)
  }

顺便说一下，我不喜欢环^^

您可以尝试：

x<-strsplit(infor[,2],";")
y<-expand.grid(x,x)
matrix(mapply(function(.x,.y)
    length(intersect(.x,.y)),y[[1]],y[[2]]),
    nrow=nrow(infor),dimnames=list(infor[,1],infor[,1]))
#    1st 2nd 3rd 4th 5th 6th
#1st   3   1   2   1   1   0
#2nd   1   4   2   0   2   1
#3rd   2   2   3   0   1   0
#4th   1   0   0   3   1   1
#5th   1   2   1   1   3   1
#6th   0   1   0   1   1   2

---

xcheck函数
？外部
function(aa, bb, Overlaps)

x<-strsplit(infor[,2],";")
y<-expand.grid(x,x)
matrix(mapply(function(.x,.y)
    length(intersect(.x,.y)),y[[1]],y[[2]]),
    nrow=nrow(infor),dimnames=list(infor[,1],infor[,1]))
#    1st 2nd 3rd 4th 5th 6th
#1st   3   1   2   1   1   0
#2nd   1   4   2   0   2   1
#3rd   2   2   3   0   1   0
#4th   1   0   0   3   1   1
#5th   1   2   1   1   3   1
#6th   0   1   0   1   1   2