ClickHouse/docs/en/sql-reference/aggregate-functions/reference/covarsamp.md

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slug: /en/sql-reference/aggregate-functions/reference/covarsamp
sidebar_position: 37
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# covarSamp

Calculates the value of `Σ((x - x̅)(y - y̅)) / (n - 1)`.

Returns Float64. When `n <= 1`, returns `nan`.

:::note
This function uses a numerically unstable algorithm. If you need [numerical stability](https://en.wikipedia.org/wiki/Numerical_stability) in calculations, use the `covarSampStable` function. It works slower but provides a lower computational error.
:::
Removed /ja folder, cleaned up /ru markdown 2022-04-09 13:29:05 +00:00			`---`
add slugs 2022-08-28 14:53:34 +00:00			`slug: /en/sql-reference/aggregate-functions/reference/covarsamp`
Removed /ja folder, cleaned up /ru markdown 2022-04-09 13:29:05 +00:00			`sidebar_position: 37`
			`---`

Remove H1 anchor tags from docs 2022-06-02 10:55:18 +00:00			`# covarSamp`
Removed /ja folder, cleaned up /ru markdown 2022-04-09 13:29:05 +00:00
			Calculates the value of `Σ((x - x̅)(y - y̅)) / (n - 1)`.

Correct return vals closes #43145 2023-02-28 17:07:11 +00:00			Returns Float64. When `n <= 1`, returns `nan`.
Removed /ja folder, cleaned up /ru markdown 2022-04-09 13:29:05 +00:00
Remove H1 anchor tags from docs 2022-06-02 10:55:18 +00:00			`:::note`
Removed /ja folder, cleaned up /ru markdown 2022-04-09 13:29:05 +00:00			This function uses a numerically unstable algorithm. If you need [numerical stability](https://en.wikipedia.org/wiki/Numerical_stability) in calculations, use the `covarSampStable` function. It works slower but provides a lower computational error.
Correct return vals closes #43145 2023-02-28 17:07:11 +00:00			`:::`