Getting index of first occurrence of a value in every column of a matrix

Question

If I have a single vector, I can get the 1st occurrence which is below a value:

test <- c(0.5,0.8,0.1,0.08,0.06,0.04)
which(test<0.1)[1]    

Answer 1

Because I just stumbled upon this, here's another solution:

max.col(t(test2 < 5), "first")