Re: how do you write aggregate function

thanks

 it now takes 806 ms

Martijn van Oosterhout wrote:

On Mon, Mar 10, 2008 at 10:01:47AM -0500, Justin wrote: 

i wish that could work  but need to keep track of the individual weights 
as its a percentage of the total amount of the weight.    

Unless you have a different meaning of weighted average to me, I don't
think you do. AFAIK this would produce exactly the same result as what
your code does:

state_function(state,weight,value) state[0] = state[0]+weight state[1] = state[1]+weight*value

final_function(state) return state[1]/state[0]

The state[0] is the same as your _sumedWeight. Because it's a constant in
the second loop you can do the division after. state[1] is your
_sumedWxV times _sumedWeight.

Have a nice day,