How do I build this custom expression in spotfire

[Kom Son]

Lets assume Ihave an excel table with three columns : SpinNumber(A), Mean (B) and Fit ©

Dynamic value cell (D)

The column row is 1

the first data row is 2

the second is 3 ..... and so on ...

The formula for SpinNumber (A) column = IF(A3 = $D$2, COUNT(C2) + A3)

How do I replicate something like this as a custom expression in spotfire Especially the part involving adding the value of the next row of a column to the value of the previous row from another column to get a new value for a new calculated column

Guidance is much appreciated!!

[Fabian Duerr]

You can use the LAG/LEAD functions to create a new column with shifted (previous or next) values. Your dynamic value ($D$2) has to be a document property. And since COUNT(of onecell) in Excel can only return 0 or 1 you can easily create another calculated column to mimic this.

So, all you need are two calculated columns and one document property to get to your final column.