%%%%%%%%%%%%%%%%%%%%% Fixed points of a Linear Fractional Transformation %%%%%%%%%%%%%%%%%%%
%
% LFTFIXEDPOINTS
% Usage: fp = LFTFIXEDPOINTS(L)
% Inputs: L in SL_2(C)     
% Output: The fixed points of L acting as an LFT

function fp = lftfixedpoints(L)
  a = L(1,1);
  b = L(1,2);
  c = L(2,1);
  d = L(2,2);
  if c == 0 
      fp = [roots([d-a,b]),inf];
  else   
  fp = roots([c,d-a,-b]);
  if abs(fp(1)) > abs(fp(2)) fp = [fp(2),fp(1)]; end;
   end;