mirror of
https://github.com/josdejong/mathjs.git
synced 2026-01-18 14:59:29 +00:00
64 lines
1.7 KiB
Markdown
64 lines
1.7 KiB
Markdown
<!-- Note: This file is automatically generated from source code comments. Changes made in this file will be overridden. -->
|
|
|
|
# Function var
|
|
|
|
Compute the variance of a matrix or a list with values.
|
|
In case of a (multi dimensional) array or matrix, the variance over all
|
|
elements will be calculated.
|
|
|
|
Optionally, the type of normalization can be specified as second
|
|
parameter. The parameter `normalization` can be one of the following values:
|
|
|
|
- 'unbiased' (default) The sum of squared errors is divided by (n - 1)
|
|
- 'uncorrected' The sum of squared errors is divided by n
|
|
- 'biased' The sum of squared errors is divided by (n + 1)
|
|
|
|
Note that older browser may not like the variable name `var`. In that
|
|
case, the function can be called as `math['var'](...)` instead of
|
|
`math.var(...)`.
|
|
|
|
|
|
## Syntax
|
|
|
|
```js
|
|
math.var(a, b, c, ...)
|
|
math.var(A)
|
|
math.var(A, normalization)
|
|
```
|
|
|
|
### Parameters
|
|
|
|
Parameter | Type | Description
|
|
--------- | ---- | -----------
|
|
`array` | Array | Matrix | A single matrix or or multiple scalar values
|
|
`normalization` | string | Determines how to normalize the variance. Choose 'unbiased' (default), 'uncorrected', or 'biased'. Default value: 'unbiased'.
|
|
|
|
### Returns
|
|
|
|
Type | Description
|
|
---- | -----------
|
|
* | The variance
|
|
|
|
|
|
## Examples
|
|
|
|
```js
|
|
math.var(2, 4, 6); // returns 4
|
|
math.var([2, 4, 6, 8]); // returns 6.666666666666667
|
|
math.var([2, 4, 6, 8], 'uncorrected'); // returns 5
|
|
math.var([2, 4, 6, 8], 'biased'); // returns 4
|
|
|
|
math.var([[1, 2, 3], [4, 5, 6]]); // returns 3.5
|
|
```
|
|
|
|
|
|
## See also
|
|
|
|
[mean](mean.md),
|
|
[median](median.md),
|
|
[max](max.md),
|
|
[min](min.md),
|
|
[prod](prod.md),
|
|
[std](std.md),
|
|
[sum](sum.md)
|