rownames and colnames with specific value

Question

I have this matrix and i want to get a 2 column matrix, where one column has the rowname and the other column, the colname of cells with value 1

x

   X1 X2 X3
         


        

Answer 1

You can do something like this :

mat <- which(x==1, arr.ind=TRUE)
mat[,"col"] <- names(x)[mat[,"col"]]
mat[,"row"] <- rownames(mat)

Which will give :

   row  col 
X1 "X1" "X1"
X4 "X4" "X1"
X2 "X2" "X2"
X3 "X3" "X2"
X1 "X1" "X3"
X3 "X3" "X3"