Prevent precision artifacts with floats in REST API #1364
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mutatrum
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cJSON has no support for floats. So when
cJSON_CreateNumberorcJSON_AddNumberToObjectis called with a float, it's upcast to double. However, this introduces precision artifacts. This PR adds two helper methods that make sure the upcast double is limited to 7 decimals, which limits superfluous digits. Upside is smaller JSON, especially for the statistics.An example:
Before:
"power": 17.9117431640625,After:
"power": 18.4124756,This is done for all floats. In some cases it cases very annoying artifacts, f.e. the float value
0.1ends up as0.10000000149011612in the JSON.I'm not super happy with the code, as it's easy to forget about this with new fields, but not sure how to make that better.