polynomial regression outside of graph?

[David Heinrich <dh003i gmail com>]

Hi all,

I like the polynomial regression inside of the chart dialog for gnumeric. I want to set up a interactive spreadsheet such that the graph and equation of the form ax^2 + bx + c changes as I change data. This works easily. However, I also want to have access to the result of the polynomial equation function's coefficients (a, b, c) changing without manually typing them over. 

The reason is because I want to setup another chart for predicted values based on the equation. But this becomes a pain if I always have to re-copy the coefficients. 

Is there a way to do this?