Trendline Graphs

[Carlo]

Hi
I have created graphs and added a trendline and then went to options
and selected to see on the graph the linear formula and R2.
I need to use the linear formula in a table elsewhere in the
spreadsheet. Is there a way to to reference the formula directly so
that when the variables in the data table are changed that it
automatically filters through to the graph and the new linear formula
is then reflected in the table elsewhere?

thanks
Carlob1

 

[Jerry W. Lewis]

See Help for SLOPE(), INTERCEPT(), and RSQ(). If you mean a linear
combination of mutiple predictors (polynomial, etc) then see Help for
LINEST().

Alternately, David Braden has posted VBA code to extract the
coefficients directly from the chart into cells

http://groups.google.com/[email protected]

The advantage of using the chart coefficients (either manually or via
Braden's code) is that LINEST (prior to Excel 2003) uses a numerically
poor algorithm that can give inaccurate results with some data sets.
The chart trendline (extracted by Braden's code) is much better
numerically, but would require VBA event programming to auto update.

Jerry