Quote Originally Posted by rsocor01 View Post
Very easy . Using data from your table and the column for Length = 13.85m,

First, plot the data as a X-Y graph. Then goto Charts -> Add Trendline. I chose a second degree polynomial for the approximation since it's clearly not a stright line. R^2=0.9993 refers to how close to been perfect is the line fitting approximation (R^2=1 is perfect).

Robert
Robert, I also tried your method and found formulas for all the columns. Now I am trying to implement them, and I am facing a problem with calculations. For example formula for my first column comes to be :

y = -875x^2 + 4375x + 2250
RČ = 1
Now my x is the radius. While calculating on excel sheet I just put 2,3,4 as radius values and their corresponding load in front. Now my actual radius is in centimeters. How do I calculate if I want for example 215 centimeters) OR (264 centimeters)? Should I make a new graph with radius in centimeters all the way from 200 to 400 or is there a better way to do it?