Subtraction within a product list

[zab]

Hello Folks

My brain is melting on this hot friday and I can't find the right way to make this calculation.

I have many many products that look like that:

id --Name -- Price $ -- Extra

001-- wall 2x4 -- 0.30

002 -- partition -- 0.50

(...)

097 -- wall 2x6 -- 0.45 -- .15

What I want is to find the PRICE difference between id 097 and ID 001 and put in in the extra field.

Price Id 097 - price Id 001 = .15

How can I do this?

I tried with filterValues, and Get(field) .... :

I will have many other to do so I guess I'm gonna start with a Case function.

The goal is to offer two plans, with one kind of value (wall) and offer a better option and show only the difference of price to pay. Of course this will be later multiplied by a quantity (per inches), Put in a portal etc.

Thank you.

[Brent Durland]

So, you have a set of records, and you want to show the price difference between the last one and the first one? If that's the case, you can use GetNthRecord for that. Use something like this:

Price - GetNthRecord ( Price ; 1 )

This would always compare the current record to the first one, so if the price for the first record is 10 and the price for the last record is 15, this field in the last record would be 5.