---
acl_categories:
- '@tdigest'
- '@read'
arguments:
- name: key
  type: key
- name: low_cut_quantile
  type: double
- name: high_cut_quantile
  type: double
categories:
- docs
- develop
- stack
- oss
- rs
- rc
- oss
- kubernetes
- clients
complexity: O(N) where N is the number of centroids
description: Returns an estimation of the mean value from the sketch, excluding observation
  values outside the low and high cutoff quantiles
group: tdigest
hidden: false
linkTitle: TDIGEST.TRIMMED_MEAN
module: Bloom
railroad_diagram: /images/railroad/tdigest.trimmed_mean.svg
since: 2.4.0
stack_path: docs/data-types/probabilistic
summary: Returns an estimation of the mean value from the sketch, excluding observation
  values outside the low and high cutoff quantiles
syntax_fmt: TDIGEST.TRIMMED_MEAN key low_cut_quantile high_cut_quantile
title: TDIGEST.TRIMMED_MEAN
---
Returns an estimation of the mean value from the sketch, excluding observation values outside the low and high cutoff quantiles.

## Required arguments

<details open><summary><code>key</code></summary> 

is the key name for an existing t-digest sketch.
</details>

<details open><summary><code>low_cut_quantile</code></summary> 
  
a floating-point value in the range [0..1]. It must be lower than `high_cut_quantile`.
  
When equal to 0, no low cut.
  
When greater than 0, exclude observation values lower than this quantile.
</details>

<details open><summary><code>high_cut_quantile</code></summary> 
  
a floating-point value in the range [0..1]. It must be higher than `low_cut_quantile`.
  
When less than 1, exclude observation values greater than or equal to this quantile.

When equal to 1, no high cut.
</details>

## Examples

{{< highlight bash >}}
redis> TDIGEST.CREATE t COMPRESSION 1000
OK
redis> TDIGEST.ADD t 1 2 3 4 5 6 7 8 9 10
OK
redis> TDIGEST.TRIMMED_MEAN t 0.1 0.6
"4"
redis> TDIGEST.TRIMMED_MEAN t 0.3 0.9
"6.5"
redis> TDIGEST.TRIMMED_MEAN t 0 1
"5.5"
{{< / highlight >}}

## Redis Software and Redis Cloud compatibility

| Redis<br />Software | Redis<br />Cloud | <span style="min-width: 9em; display: table-cell">Notes</span> |
|:----------------------|:-----------------|:------|
| <span title="Supported">&#x2705; Supported</span><br /> | <span title="Supported">&#x2705; Flexible & Annual</span><br /><span title="Supported">&#x2705; Free & Fixed</nobr></span> |  |

## Return information

{{< multitabs id="tdigest-trimmedmean-return-info" 
    tab1="RESP2" 
    tab2="RESP3" >}}

One of the following:

* [Bulk string reply]({{< relref "/develop/reference/protocol-spec#bulk-strings" >}}) as a floating-point estimation of the mean value.
* `nan` if the sketch is empty.
* [Simple error reply]({{< relref "/develop/reference/protocol-spec#simple-errors" >}}) in these cases: the given key does not exist or is of an incorrect type, quantiles out of range [0..1], or incorrect number of arguments.

-tab-sep-

One of the following:

* [Double reply]({{< relref "/develop/reference/protocol-spec#doubles" >}}) as an estimation of the mean value.
* `nan` if the sketch is empty.
* [Simple error reply]({{< relref "/develop/reference/protocol-spec#simple-errors" >}}) in these cases: the given key does not exist or is of an incorrect type, quantiles out of range [0..1], or incorrect number of arguments.

{{< /multitabs >}}