Triggering events for objects at certain point

I have some dogs that I spawn on either the left hand side, or the right hand side. When they are created I give an instance variable a value of int(random(48, 592)) and they run across the screen. I am trying to trigger a series of events when the dogs reach an x position of int(dog.x) = dog.pooSpot Currently, I am doing it like so:<img src="http://i.imgur.com/3lqJJQa.png" border="0" />

however, it's not getting all the dogs to go poo. How can I make sure they all do it?

the dog is probably passing over the pooSpot so the condition is never met

if the pooSpot.x is 200 for example..

the dog.x might go from 198 to 202 in a single tick.. it depends on its speed

a way around this would be to change

pspot = int(dog.x)

to

system| is inbetween values:

pspot.x-16 > dog.x > pspot.x+16

this means if the dog is within 16 px of the spot, the condition is met.

That makes perfect sense, thanks a bunch.