Extracting Trendline Coefficients

R

rodwellm

I am trying to use Tushar Mehta's version of the trendline coefficient
extraction code, which I found here:
http://www.tushar-mehta.com/publish_train/data_analysis/16.htm
My problem is that for some reason if I save the file and reopen it,
Excel locks up and the TLcoef and TLeval formulas return "Err: No
trendline found"

What is wrong? Should I be changing something in the code?

FYI - i'm using Excel 2002.
 
B

Bernard Liengme

Why not use one of his LINEST formulas to get the coefficients?
best wishes
 
R

rodwellm

The LINEST formulas in Excel 2002 and previous aren't as good as the
chart trendline for complex data. This is why I need to extract the
trendline data.
 
B

Bernard Liengme

Agreed, there are cases when LINEST gives incorrect results.
I would be interested in seeing such a data set.
best wishes
 
J

Jerry W. Lewis

I presume that you want to see if the OP has a new example; that would
interest me as well.

Previously posted examples include

http://groups.google.com/group/microsoft.public.excel/msg/969a2bb33e6cdbb8
a 6th degree polynomial fit that gets no correct figures in versions prior
to 2003, but does better in 2003 on.

http://groups.google.com/group/microsoft.public.excel.charting/msg/438ea066b144d042
a 6th degree polynomial fit that gets no correct figures in any version of
Excel

http://groups.google.com/[email protected]
an orthogonal trigonometric regression that worked prior to 2003, but gives
erroneous zeros in 2003.

Jerry
 
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