r - Creating a matrix from data frame -

i have data frame df1 5 columns c1, c2, c3, c4, , c5:

df1 <- data.frame(c1 = c(1, 0, 1), c2 = c(0, 0, 1), c3 = c(2, 1, 0), c4 = c(1, 4, 3), c5 = c(1, 0, 0))     #df1   c1 c2 c3  c4  c5   1  0  2   1   1   0  0  1   4   0   1  1  0   3   0  

my desired output is:

  1  3  3   4  5   3  4  4   4  4   1  2  4   4  4 

basically, creating matrix based on column number , value (value less or equal 5). example, 2nd row in df1 has 1 , 4 belongs column c3 , c4. so, 2nd row in desired matrix 3 4 4 4 4.

i have tried myself. code involves several nested control flows , not working large data frame.

a little apply magic:

t(apply(df, 1, function(x) rep(row(as.matrix(x)), x))) #     [,1] [,2] [,3] [,4] [,5] #[1,]    1    3    3    4    5 #[2,]    3    4    4    4    4 #[3,]    1    2    4    4    4