6
    1-----------------
         1         0         0
         0         1         0
         0         0         1
    2-----------------
         0         0         1
         1         0         0
         0         1         0
    3-----------------
         0         1         0
         0         0         1
         1         0         0
    4-----------------
         0         1         0
         1         0         0
         0         0         1
    5-----------------
         1         0         0
         0         0         1
         0         1         0
    6-----------------
         0         0         1
         0         1         0
         1         0         0
 -------------------------------

*******************************************
Symmetry operation files generated from "kpgen". 
They are in the unit of supercell lattice AL(3,3). (Not in the unit of x,y,z). 
Each operation is a matrix of integer. 
The symmetry is just a point group symmetry around the origin. So, it is 
important to shift the highest symmetry point to the origin in atom.config
The inversion operation is omitted, since k -> -k relationship already exists
in a calculation without magnetic field. The PEtot and k-point reduction do not 
take further advantages over the spacial inversion symmetry.