[Pw_forum] Fwd: different symmetry when using equivalent representation

[Lorenzo Paulatto]

Replying to message "[Pw_forum] Fwd: different symmetry when using  
equivalent representation" from Jess Kondor (17/12/09):
>  I have some trouble in understanding why equivalent (if I am not
> wrong) representation of the crystal structure leads to different
> symmetry (as shown in the output from pw.x). All input/output
> files are attached.

Dear Jess,
the code threshold for checking the symmetry is too strict for the number  
of significant digits you have specified for the basis vectors (I see you  
have copied them from the output of test1.inp, but apparently it is not  
enough).

You recover all 6 symmetry operations if you specify the cell parameters  
with more digits, e.g.
    0.502718227240668  -0.290244503823931   0.814268083618657
    0.000000000000000   0.580489007647862   0.814268083618657
   -0.502718227240668  -0.290244503823931   0.814268083618657

best regards

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Lorenzo Paulatto
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