use like this :
./plot_phase.py path/to/simulation/P_Opsi.dat \
-s path/to/simulation/res.png \
-o path/to/simulation/res.json \
--radius 5.0 --width 1.2 \
--delta_y 0.07 --delta_z 0.07 \
--number_samples_y 280 \
--number_samples_z 450 \
--snap 1000
res.png
will contain the phase curvesres.json
will contain the winding numbers so that they can be easily loaded and analysed with any language later