[PD] selecting triggers once with env~?

[Ronni Montoya via Pd-list]

Hi, im tracking the amplitude of my signal with ~env and i need to
send one trigger when my ~env gives 0 , the problem is that if i do:

~env
   |
select 0


It send a lot of triggers when my ~env is in 0 and i need to send just
one trigger.

any idea how can i send only one trigger ?




thanks


R,