I'd like to increase the number of displayed digits in a nonlinear trendline, e.g. polynomial degree > 1. Can't find a way. Using linest it can be done in a table. Higher order I think I am out of luck.
[Re-Titled by Moderator]
Mac mini, macOS 15.5
You can use LINEST to get the exponents of other trendlines. Here is an example for a 3rd order polynomial.
Data for the chart is in columns B and C
Columns D-F are what they say in the header, using formulas
Formula in cell G2 =LINEST(C,D:F,,TRUE)
In the current version of Numbers, this will spill into all the rest of the cells, showing you the entire array of values in LINEST. The first row of these values has the coefficients. In earlier versions, you use INDEX along with LINEST to get each value.
You can use LINEST to get the exponents of other trendlines. Here is an example for a 3rd order polynomial.
Data for the chart is in columns B and C
Columns D-F are what they say in the header, using formulas
Formula in cell G2 =LINEST(C,D:F,,TRUE)
In the current version of Numbers, this will spill into all the rest of the cells, showing you the entire array of values in LINEST. The first row of these values has the coefficients. In earlier versions, you use INDEX along with LINEST to get each value.
For other trendlines you make them into linear equations. Use INTERCEPT and SLOPE to get the coefficients of the linearized equations then convert them back to the original equation.
Power, as an example:
y = a*x^b
Want to find a and b
log(y)=log(a*x^b)
log(y) = log(a) + log(x^b)
log(y) = log(a) + b*log(x)
log(y)=b*log(x) + log(a) <<--this is a linear equation in terms of log(y) and log(x)
Make a column for log(y) and log(x) and use INTERCEPT and SLOPE on them.
The slope is b and will be correct as is
The intercept will be log(a). Convert it. 10^log(a) = a
How can I increase the number of displayed digits in a nonlinear trendline?
