% Define a function to drive to zero. Input arg is the independent vars.
function F = fit(x,f,Vc)
  % Can redefine independent vars for more meaningful names
  RF = x(1);
  CF = x(2);
  LF = x(3);
  % Return function evaluation at input vin, column vector.
  % Arrange so function = zero (ie. subtract eqn left side from right)
  Zl = j*2*pi*f*LF;
  Zc = 1./(j*2*pi*f*CF);
  
  F = Vc - (Zc ./ (RF + Zl + Zc));
  % Separate real/imag columns so both are driven to zero
  F = [real(F), imag(F)];
endfunction