lambda=direction_cosine(theta,phi,chi)

function lambda=direction_cosine(theta,phi,chi)

lambda(1,1)=cos(theta)*cos(phi)*cos(chi)-sin(phi)*sin(chi);
lambda(1,2)=cos(theta)*sin(phi)*cos(chi)+cos(phi)*sin(chi);
lambda(1,3)=-sin(theta)*cos(chi);
lambda(2,1)=-cos(theta)*cos(phi)*sin(chi)-sin(phi)*cos(chi);
lambda(2,2)=-cos(theta)*sin(phi)*sin(chi)+cos(phi)*cos(chi);
lambda(2,3)=sin(theta)*sin(chi);
lambda(3,1)=sin(theta)*cos(phi);
lambda(3,2)=sin(theta)*sin(phi);
lambda(3,3)=cos(theta);