Export quantile functions
For use in Mimir's query engine, it would be helpful if these
functions were exported.
Co-authored-by: Björn Rabenstein <github@rabenste.in>
Signed-off-by: Joshua Hesketh <josh@hesketh.net.au>
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Signed-off-by: Joshua Hesketh <josh@nitrotech.org>
Signed-off-by: Joshua Hesketh <josh@hesketh.net.au>
Co-authored-by: Björn Rabenstein <github@rabenste.in>
promql: Improve histogram_quantile calculation for classic buckets
Tiny differences between classic buckets are most likely caused by floating point precision issues. With this commit, relative changes below a certain threshold are ignored. This makes the result of histogram_quantile more meaningful, and also avoids triggering the _input to histogram_quantile needed to be fixed for monotonicity_ annotations in unactionable cases.
This commit also adds explanation of the new adjustment and of the monotonicity annotation to the documentation of `histogram_quantile`.
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Signed-off-by: Jeanette Tan <jeanette.tan@grafana.com>