%%%%%%%%%%%%%%%%%%%%% Schwartz Quadrilateral Constructor %%%%%%%%%%%%%%%%%%%%%
%
% QSCHWATRZ1
% Usage: QSCHWATRZ1(s,t,u,v,h)
% Inputs:  s,t,u,v  - real numbers with 1/s +1/t + 1/u+ 1/v < 2 
%          h  - sidelength h must satisfy:
%          cosh(h) > (cos(a)*cos(b)+1)/(sin(a)*sin(b))
%          where a = pi/s, b = pi/t
%
% Output: matrix of numbers [ 0, L, z,w] such that  L is a positive real, 
%         the hyperbolic angles at the vertices are given by
%       
%               vertex         hyperbolic angle   
%
%                  0                pi/s             
%                  L                pi/t
%                  z                pi/u            
%                  w                pi/v       
%         and the hyperbolic length from 0 to L is h

function Q = qschwartz1(s,t,u,v,h)             

 Q = qschwartz(s,t,u,v,h);
 L = lft([-1,Q(1),1],[-1,0,1]);
 Q = lftact(L,Q);