Calculate the Stokes parameters in detector coordinates for the input event file 'ixpe00000000_det1_evt1_v01.fits'.
The results are written in 'DETPHI', 'DETX', 'DETY', 'DETQ' and 'DETU' columns of the output event file
'ixpe00000000_det1_evt1_v01_out.fits'.
> ixpecalcstokes infile=ixpe00000000_det1_evt1_v01.fits outfile=ixpe00000000_det1_evt1_v01_out.fits