Symmetry operations for the point group Cs (m) 
1 : x,y,z           => 1                   

[[ 1.  0.  0.]
 [ 0.  1.  0.]
 [ 0.  0.  1.]]

2 : x,-y,z          => m [ 0 1 0 ]         

[[ 1.  0.  0.]
 [ 0. -1.  0.]
 [ 0.  0.  1.]]

Irreducible representations for the point group Cs (m) 
Irrep A' ( dimension  1 )
1 : 1.0                 

2 : 1.0                 

Irrep A'' ( dimension  1 )
1 : 1.0                 

2 : -1.0                

