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diff --git a/web/api/queries/median/README.md b/web/api/queries/median/README.md deleted file mode 100644 index f1fb3a61c..000000000 --- a/web/api/queries/median/README.md +++ /dev/null @@ -1,64 +0,0 @@ -<!-- -title: "Median" -sidebar_label: "Median" -description: "Use median in API queries and health entities to find the 'middle' value from a sample, eliminating any unwanted spikes in the returned metrics." -custom_edit_url: https://github.com/netdata/netdata/edit/master/web/api/queries/median/README.md -learn_status: "Published" -learn_topic_type: "References" -learn_rel_path: "Developers/Web/Api/Queries" ---> - -# Median - -The median is the value separating the higher half from the lower half of a data sample -(a population or a probability distribution). For a data set, it may be thought of as the -"middle" value. - -`median` is not an accurate average. However, it eliminates all spikes, by sorting -all the values in a period, and selecting the value in the middle of the sorted array. - -Netdata also supports `trimmed-median`, which trims a percentage of the smaller and bigger values prior to finding the -median. The following `trimmed-median` functions are defined: - -- `trimmed-median1` -- `trimmed-median2` -- `trimmed-median3` -- `trimmed-median5` -- `trimmed-median10` -- `trimmed-median15` -- `trimmed-median20` -- `trimmed-median25` - -The function `trimmed-median` is an alias for `trimmed-median5`. - -## how to use - -Use it in alerts like this: - -``` - alarm: my_alert - on: my_chart -lookup: median -1m unaligned of my_dimension - warn: $this > 1000 -``` - -`median` does not change the units. For example, if the chart units is `requests/sec`, the result -will be again expressed in the same units. - -It can also be used in APIs and badges as `&group=median` in the URL. Additionally, a percentage may be given with -`&group_options=` to trim all small and big values before finding the median. - -## Examples - -Examining last 1 minute `successful` web server responses: - -- ![](https://registry.my-netdata.io/api/v1/badge.svg?chart=web_log_nginx.response_statuses&options=unaligned&dimensions=success&group=min&after=-60&label=min) -- ![](https://registry.my-netdata.io/api/v1/badge.svg?chart=web_log_nginx.response_statuses&options=unaligned&dimensions=success&group=average&after=-60&label=average) -- ![](https://registry.my-netdata.io/api/v1/badge.svg?chart=web_log_nginx.response_statuses&options=unaligned&dimensions=success&group=median&after=-60&label=median&value_color=orange) -- ![](https://registry.my-netdata.io/api/v1/badge.svg?chart=web_log_nginx.response_statuses&options=unaligned&dimensions=success&group=max&after=-60&label=max) - -## References - -- <https://en.wikipedia.org/wiki/Median>. - - |