r - find the max frequency per row in a matrix whith multiple max -

i have matrix this:

mat=matrix(c(1,1,1,2,2,2,3,4,          4,4,4,4,4,3,5,6,          3,3,5,5,6,8,0,9,          1,1,1,1,1,4,5,6),nrow=4,byrow=true) print(mat)       [,1] [,2] [,3] [,4] [,5] [,6] [,7] [,8] [1,]    1    1    1    2    2    2    3    4 [2,]    4    4    4    4    4    3    5    6 [3,]    3    3    5    5    6    8    0    9 [4,]    1    1    1    1    1    4    5    6 

i find out number of row of matrix in can find objects max frequency, have more 1 max. in case, obtein new vector this:

     [,1] [1,] "1"  [2,] "3"  

or similar. focus on index of row more 1 max.

we can use apply margin=1 loop on rows. frequency of each unique element tabulate, check whether equal max value (==) , use which numeric index. return max value if there ties.

lst <- apply(mat, 1, function(x) {x1 <- tabulate(x)                  which(x1 == max(x1))      }) 

if there single max value per row, output vector or else list output.

if need extract elements have more 1 max

lst[lengths(lst)>1]