Dear matlab friends: I have two very complicated eqns, like this: x = f(x,y) y = f'(x,y) both f and f' are very very complocated, for example f(x,y) = cosxy + siny +y/28*e^xy+ log(x/y^1.41)+.... I cannot use "solve" to solve it cause it seems take forever to get the solution. How to write a code to solve these two eqns? I wrote a fix-point iteration code to solve one unknown with one eqn. But I don't know how to write a code for several unknown variables. Any suggestion is welcome. Thanks & Best Regards Yi