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BUG: Python's PprzMessage doesn't cast values to the specified types

Open MJafarMashhadi opened this issue 4 years ago • 2 comments

msg[value_name] is always of type str and the fieldtypes property is ignored there (at least for numbers). It's only used when converting to/from binary.

MJafarMashhadi avatar Jul 09 '20 05:07 MJafarMashhadi

Yes, it is true that data in message fields have the same type than the element stored inside. So when they are filled from IVY strings, I guess they all end up as str as well. It's not really a bug, nor a feature... Mostly laziness I guess :( If you have a clean solution for that, it could be integrated, as there is no reason to store data with the wrong type. And that would avoid explicit cast when extracting them on user side (like here: https://github.com/paparazzi/paparazzi/blob/master/sw/ground_segment/python/multi/fc_rotor/fc_rotor.py#L116)

gautierhattenberger avatar Jul 09 '20 21:07 gautierhattenberger

Explicit casting was exactly what I had to do as well!

I think doing the type casting right in ivy_string_to_payload and binary_to_payload would do the job. Also it'd be nicer to have a dictionary mapping names to a 3-tuple of value, dtype, and coef instead of keeping 4 separate lists in-sync for them.

MJafarMashhadi avatar Jul 09 '20 22:07 MJafarMashhadi