Trendline Equations

[swissforestry]

Hello~

Is there a way to have a cell state the "Trendline Equation" from a
chart? I can get the chart to display the equation, but so far I have
to manually input the formula to a cell if I want to use it. I would
like to bypass this, so I don’t have to change the Equation if I change
the data in the chart.

Alternatively, can you have a function that recognizes the variables in
the equation, and just reference it from the chart? So in this case i
would want to have a formula that would identify the trendline equation
and also identify the x,y: i.e B4 = (X) and B5 = (y). Then i could drag
it down the column for each row.

make any sense??

thanks~

 

[Gary''s Student]

Your question makes a lot of sense. Look for help on LINEST to see if it can
help you.

 

[Ron Rosenfeld]

Hello~

Is there a way to have a cell state the "Trendline Equation" from a
chart? I can get the chart to display the equation, but so far I have
to manually input the formula to a cell if I want to use it. I would
like to bypass this, so I don’t have to change the Equation if I change
the data in the chart.

Alternatively, can you have a function that recognizes the variables in
the equation, and just reference it from the chart? So in this case i
would want to have a formula that would identify the trendline equation
and also identify the x,y: i.e B4 = (X) and B5 = (y). Then i could drag
it down the column for each row.

make any sense??

thanks~

If you have Excel 2003, you can probably use the LINEST worksheet function
safely. It is available in earlier versions, but others have written that the
algorithm is not as robust in earlier versions.

David Braden posted some VBA code a few years ago that can extract the
coefficients from a chart. The chart trendline algorithm is different from the
LINEST algorithm, and is felt by others to be quite stable. See:

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

or

http://groups.google.com/group/microsoft.public.excel.misc/msg/4d440d271303e0d6

or

http://tinyurl.com/8ozq9


--ron