Extracting Polynomial equation formula from trendline

[#1]

Hi,

I am trying to build a table with a forecast column using the values from the polynomial trendlines and then extract the formula (i.e. y = a2x^2 + a1x + b).

I know how to do this for linear trendline (y=mx+b), using:

m = LINEST_M(Aggr(sum(Xval),Yval),Yval)

b = LINEST_B(Aggr(sum(Xval),Yval),Yval)

I can then use these values in straight table to make a forecast column in my table. However, this is less acurate than the polynomial equation. Are there  equvilent functions to calculate the polynomial constants?

Thanks in advance,

Dave

[Gysbert_Wassenaar · Accepted solution]

No, that's not possible. But you can add a polynomial trendline of 2nd to 4th degree and check the option Show Equation. If you need more statistic functions you need something like the R integration kit.

[#3]

Ok, thanks!