If I understand your question, the Add Trendline dialog has an Options
tab where you can ask for the equation for the trendline to be
displayed. You can then copy the coefficients (format to scientifice
with 14 decimal places to avoid rounding away needed precsion) from the
displayed equation and use them in a cell formula to calculate values.
David Braden has posted code
http://groups.google.com/[email protected]
to automate copying these coefficients.
Most chart trendlines can also be recalculated via
- SLOPE() & INTERCEPT() or FORECAST() for straight lines
- LINEST() or TREND() for multiple linear predictors (including
polynomials)
- LOGEST() or GROWTH() for single or multiple exponential predictors
Jerry