Fastet way to position a double in an existing vector

Question

Let's say I have a double like 3.5 and I would like to find out where to sort it in an existing sorted vector say seq(1, 10), put differently, which index the new number would take in the vector. Of course it sits somewhere between 3 and 4 and hence between the third and fourth index, but what would be the fastet way to arrive at this result?

Answer 1

Something like this?

First define dbl and my_seq then concatenate both with c(dbl, my_seq) and wrap it with sort

then define the index with which(my_vec == dbl):

dbl <- 3.5
my_seq <- seq(1,10)
my_vec <- sort(c(dbl, my_seq))
index <- which(my_vec == dbl)
index

output:

[1] 4