Non linear simultaneous equations into a matrix and solve

[brendanc203]

looking for help. I've basically got a system the generated a system of non linear equations that are circle equations. It represents a coordinate system plotting bearings positions of a mechanical machine. The issue being I don't know how to solve these I've only been able to print the actual formula into the cells but as the all depend on each other they cant solve without a guess. Any advice would be welcomed.

all the if statements add more equations although these probably aren't needed.

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[MrShorty]

I am having a difficult time reverse engineering what you are doing here. I can see a lot of equations that look something like z=(l^2-(y1+y2)^2)^0.5-x1. I also did not spend enough time trying to reverse engineer what your VBA code is doing.

If it helps, I would expect to use a numerical procedure similar to that described here: http://www.csun.edu/~lcaretto/me309/11-solvingSNLAE.pdf

1) Arrange all equations so they are in the form fk(unkowns)=0
2) Enter my initial guesses for unkowns
3) Enter my fk(unkowns) formulas
4) Enter a cell (my future "objective function) that is the sum of the squares of fk(unkowns) (=SUMSQ(fk))
5) Call up Solver and tell it to:
5a) Set Target cell: objective function from step 4
5b) To a value of 0 (or to a minimum -- should be the same thing)
5c) By changing: the unknown values
5d) Subject to any constraints.
6) Evaluate Solver's solution to make sure it is reasonable.

VBA would not be needed using this kind of approach.

[shg]

Maybe you could explain what all that means and what you're trying to do.

[brendanc203]

basically need aid in creating a matrix of all the equations that the VBA creates. My VBA knowledge is very poor. And although I know the steps I need to solve a matrix of non-linear equations (my circle equations) how to code this I am having difficulty with, this is a lot to do with the equations being variable depending on the type of machine which alters the arrangement of variables. This is very hard to explain so any questions I'll try my best to answer