
7: on echo;

8: off exp;

9: 
9: % a programme to calculate the surface energy tensor or the Curzon field in
9: % quasi-cylindrical coords. The surface is a cylinder x(0)=time, x(1)=azimuthal angle,
9: % x(2)=radial, x(3)=axial.
9: 
9: operator q, x, y, z;

10: for all i,j such that i neq j
10:    let {df (x (i), x(j)) => 0,
10:       df (y(i), y(j)) => 0,
10:       df (q(i), q(j)) => 0};

11: 
11: array g(3,3), gp(3,3), h(3,3), cs1(3,3,3), cs2(3,3,3),
11:    n(3), twop(2,2), two(2,2) ;

12: 


13: 
