I am writing an analysis routine that will mainly use the heart_rate and power data during a cycling. I created a .csv file of a representitive example .fit file from a Fenix 5 with Quarq power sensor on the bike to use while developing/debugging. My message listener pays most attention to the 'RECORD' (20), which appears to have most of the data of interest. In the .csv file, there are columns 'Type' and 'Local Number' that appear in the list of RECORD messages. Type is either 'data' or 'definition', which is pretty clear, so I focus on 'data'. But the 'Local Number' takes on a 8 different values, some only have one or two entries, others have quite a few (1000s). It seems the timestamp values go pretty much in order (second-by-second). Picking intermediate values, they only appear once, but the first and last timestamp appear 12 and 9 times, respectively. The messages with different 'Local Number' have somewhat different contents, i.e. their list of data types is different. But I do not see 'Local Number' in contents of a message in the python code. I note that Local Number' = 13 appears at the beginning of the RECORD list, then when it changes to 15, we get fields 'accumulated power', etc, then when it changes to 0, I now have 'left-right-balance'.
How do I make sense of the 'Local Number', and should I be ignoring one or more of those in my python code? If so, how do I do that?
