excel solver like Public Function

You can access worksheet function through the Worksheetfunction property (Application.worksheetfunction.match(arguments). I thought there was a list of worksheet functions available to VBA in the VBA help files. Try putting something like worksheet functions available to VBA in the VBA search engine and see if it comes up.

The match function is commonly called from VBA. The others, not so much, probably because the .cells(i,j) property/method usually works just as well without needing the worksheet function version.

I have a function that has 3 variables ( f(x,y,z) = 2X + y^2 + 1/z ) that i would like to compare to a set of values that i will call "observed values f(obs)"... i would like to find the values for x, y, and Z that will minimize the sum of squares....

please see the attachment for the equation

minimize.JPG

how do i do this optimization problem?
just to be clear...f(obs) are just values listed in Column A...like 1.5, 1.6, 1.8, 1.9, 2.5, 3.6, 5.4, 8, 9.1 ...etc