Differences among multiple ways of injecting users

Hi all,

I was reading the injection part of the documentation and saw this for rampUsers:
Injects a given number of users with a linear ramp over a given duration.

does that mean:

rampUsers(x * y) over (y)


is the same as

constantUsersPerSec(x) over (y)

also is

rampUsers(x) over (0)

same as


First is yes, second is no.