I have a list of coordinates (x,y) and need to determine the average mean radius for these coordinates. I don't know the excel formula to use to do this. Can somebody please help.
Thanks.
If these are Cartesian (x,y) coordinates and the centre for your radius
is the origin (0,0), then the radius is
=sqrt(x^2+y^2).
[Pythagoras: triangle with sides r, x and y.]
eg if A1:A10 and B1:B10 contain your x and y coordinate pairs: Put
=sqrt(A1^2+B1^2) in C1 and copy down to C10.
In C11 put =average(C1:C10).
If that isn't a proper interpretation of your needs, come back!
I have only seen this done thru iteration. Excel's Solver does a really
good job of finding a central x & y coordinate. I find that if I minimize
the sum of the Standard Deviation of the Radius ^2, then Solver finds a good
solution with test data. You could then take the average of the radius if
that is appropriate.
HTH
Dana DeLouis
erich said:
I have a list of coordinates (x,y) and need to determine the average mean
