NETLOGO: Using variable from previous tick

问题:

is there some primitive for using value of variable from previous tick? I tried to compute variable of "price" for one agent and I mean to use formula which includes other agents' "price" variable but from previous tick.

回答1:

No, there is no built-in way to do this in NetLogo. Your best bet would probably be to create a variable called something along the lines of varname-last-tick and then updating that as the last thing you do in the go procedure of these agents. It sounds like the variable you want to use for your agents is 'price', so it would be something like,

to agent-go
  do-stuff
  set price-last-tick price
end

then you can use [price-last-tick] of other agents in your code rather than the current price.