Macro Gurus-Accumulating Totals

[Renerabbitt]

I am learning macros, at a decent pace, but this consistantly eludes me. 
I would like to see a WORKING and COMPLETE example of a macro that accumulates totals which includes an individual publisher with a count greater than 1.
Example, I want to assign the value of 20 to a custom field on an object, and add it to an accumulating total from other publishers that have values in that same custom field. Then report the count and also the total to global macros so I can use them in other calcs.
Everytime I try and make this work, the accumulation compounds for every redraw, despite me putting in a step for resetting the totals.

[SHCanada2]

if you have a unique id for the object (such as a schedule number), the label can add the value to an array which has the unique id. so before adding it to the array, you check to see if it is there first. if it is, you update, if not you add. I think joe uses ObjectId as the unique identifier

 

The only downside is when an item is removed, or if the unique ID changes. I have not found a great solution. One is to reset the whole thing and let it repopulate the array

[SHCanada2]

so something like:

 

 

..manage initialization and setting of variables...

 

i = 0

j = $Array1.length

lfound = false

while i < j

if $Array1[i][0] == owner.schedule_number

$Array1[i]= [owner.schedule_number,@customfield]

lfound = true

end

i = i+1

end

 

i=$Array1.length

if lfound == false

$Array1[i] = [owner.schedule_number, @customfield]

end

 

The above assumes there are no duplicate objects with the same schedule number