Originally Posted by

**LayMuon** I have a function which depends say upon two variables: f(x,y).

I need to find numerically the solution line y(x) of the equation f(x,y)=0. The function itself for arbitrary set of {x,y} may evaluate to some complex number (it involves lots of square roots) but for the solution I am seeking the imaginary part on the solution line should be zero. I understand that one in principal can scan through the whole region of {x,y} to get the curve but I need numerically efficient way to write the code.

Thanks.