Re: how do you write aggregate function

[Justin <justin@xxxxxxxxxxxxxxx>]

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. 

I would never have thought the performance of the Array would suck this bad. 

Martijn van Oosterhout wrote:

On Sun, Mar 09, 2008 at 11:40:47AM -0500, Justin wrote:
  

I got the aggregate function for weighted average done.   I finely left 
alone for more than 10 minutes  to actual get it written.  It takes 2 
value input  Weight and the Value.  it will sum the weighted entries to 
create the constant then does the normal formula, but does not 
percentage number but averaged number.  A simple change on the return 
line it can do percentages.
    

If you're looking for performance, ISTM the best option would be to
simply accumulate the weights and value*weight as you go and do a
division at the end. That seems likely to beat any implementation
involving array_append.

Have a nice day,