@Nicolas HUOT, sorry for the late reply.
As mentioned in the help section of the code, the origin of polar coordinate system is top left corner of the image and the rho can not be negative, so I think the code already covers the entire span. Please let me know if I am missing something.
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@ines, the new version should be corrected for that error. please try it out. You should not have any problem now unless you are using a very large image with very small increment for pdetect that causes the size of pdetect to increase drastically.