function [fi,psi,alfa,teta,iy,iv,iseed] = angles(nmodes,iseed,iy,iv)
%function [fi,psi,alfa,teta,iy,iv] = angles(nmodes,iseed,iy,iv) %corrected 11 May 2014

ang=zeros(nmodes,1);

[fi,iseed,iy,iv]=randf_1(nmodes,0,2*pi,iseed,iy,iv);
[psi,iseed,iy,iv]=randf_1(nmodes,0,2*pi,iseed,iy,iv);
[alfa,iseed,iy,iv]=randf_1(nmodes,0,2*pi,iseed,iy,iv);
[ang,iseed,iy,iv]=randf_1(nmodes,0,1,iseed,iy,iv);
for m=1:nmodes
% ang lies in the intervall 0 < ang < 1; make teta lie in the intervall  0 < ang < pi
%  acos(a)=asin(-a)+pi/2
    teta(m)=acos(1-ang(m)/0.5); 
end