- Using log() to indicate natural log can add some confusion when trying to further adjust/tweak scores. Other parts of the API (field_value_factor on this same page) use 'ln' and 'log', so this change should be more consistent
- Fixes#20027
- I generated the images using http://latex2png.com/ at a resolution of 150 which seemed to be about the same size as before
This aggregation computes unique term counts using the hyperloglog++ algorithm
which uses linear counting to estimate low cardinalities and hyperloglog on
higher cardinalities.
Since this algorithm works on hashes, it is useful for high-cardinality fields
to store the hash of values directly in the index, which is the purpose of
the new `murmur3` field type. This is less necessary on low-cardinality
string fields because the aggregator is smart enough to only compute the hash
once per unique value per segment thanks to ordinals, or on numeric fields
since hashing them is very fast.
Close#5426
Greg Ichneumon Brown
Adrien Grand
Clinton Gormley
gmarz
Zachary Tong
Colin Goodheart-Smithe
Matias Tealdi
Britta Weber
Costin Leau