The short answer is: you probably shouldn't.
It's just a bad idea to go through a series of potentially hundreds of particles per particle created.
In my case, I just wanted to know how to set it up (if it's possible). I want to sample a total of 5 (non-loop) particles for a film, and I'm the one who controls the amount produced so the cost isn't a risk factor for me.
You build your algorithm to use n samples per particle and use this short sample to guess the actual value. This will make your algorithm inaccurate, but possibly fast enough to be viable in the game.
Sorry i'm not sure i follow algorithm? I'm just looking for something that I can enter in my "Particle Index" so that I can sample 5 particles simultaneously instead of 1 simultaneously. Is that possible?
You pre-calculate values for your set of particles outside the particle execution phases (BP in the case of unreal). However, this only really works if the values you need for the particles are consistent across all particles.
I feel very slow today. What values do you refer to? The only thing I need is a way that the Particle Index input will include my total amount of particles created. Again, if it is possible.