Iterative Process - While Loops

I am trying to write a program that will take an initial guess for my variable h6_guess and run it through a series of equations until my new value for h6, h6_mod, is equal to the value guessed.

I would like to use a while loop in order to change the value of h6_guess each time and then run it through the same equations until it returns a value equal to the original guess.

Some advice on this topic, general methods/code, or places to look for examples would be greatly appreciated.

[sixwwwwww]

Can you tell which equation you want to solve for this iteration process? You can refer to this as well for using while loop in for convergence problem: http://www.mathworks.de/matlabcentral/answers/89584-help-a-noob-implement-matlab-for-a-math-iteration