%%%%%%%%%%%%%%%%%%%%% Hyperbolic distance %%%%%%%%%%%%%%%%%%%%%
%
% HDIST
% Usage: HDIST(x,y)
% Inputs:  x,y points inside or on the unit circle 
%
% Outputs: the hyperbolic distance between x and y

function h = hdist(x,y)             
   b = abs((y-x)/(1-conj(x)*y));
   h = log((1+b)/(1-b));