48 lines
808 B
Markdown
48 lines
808 B
Markdown
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## `STD_DEV` [esql-std_dev]
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**Syntax**
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:::{image} ../../../../../images/std_dev.svg
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:alt: Embedded
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:class: text-center
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:::
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**Parameters**
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true
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**Description**
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The standard deviation of a numeric field.
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**Supported types**
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| number | result |
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| --- | --- |
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| double | double |
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| integer | double |
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| long | double |
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**Examples**
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```esql
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FROM employees
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| STATS STD_DEV(height)
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```
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| STD_DEV(height):double |
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| --- |
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| 0.20637044362020449 |
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The expression can use inline functions. For example, to calculate the standard deviation of each employee’s maximum salary changes, first use `MV_MAX` on each row, and then use `STD_DEV` on the result
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```esql
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FROM employees
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| STATS stddev_salary_change = STD_DEV(MV_MAX(salary_change))
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```
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| stddev_salary_change:double |
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| --- |
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| 6.875829592924112 |
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