Hi
How can I compute cummulative sum and store it in an expression? and I would like to use that expression for further computation.
date $(value)
1/1/2011 5
1/2/2011 10
1/3/2011 8
The expression should yield
date newexpression
1/1/2011 5
1/2/2011 15
1/3/2011 23
Note: the columns value is an expression
I dont want to
($(value)+if(isnull(above("newexpression")),0,above("newexpression")))
This works fine only if i have a column called newexpression in my straightable. But i dont want to have this as a column, I want to be able to store this in an expression and i have to do further computation.
what should I be doing instead?