# 3.5.2.7 Cov

## Description

This function returns the covariance between two datasets. Let X and Y be two datasets and $\bar{x}$ and $\bar{y}$ their respective means, then the covariance between the two is defined as:

$cov(x,y,\bar{x},\bar{y})=\frac{1}{n-1}$$\sum_{i=1}^\mathit{n}$$(x_i-\bar{x})(y_i-\bar{y})$

## Syntax

double cov(dataset vx, dataset vy[, double avex, double avey])

## Parameter

vx

A dataset, or a range pointing to a single dataset.

vy

A dataset, or a range pointing to a single dataset.

avex

Mean of dataset vx.

avey

Mean of dataset vy.
 Note: In Origin 92, avex and avey can be omited when setting parameters. Their default values are the average of vx and vy datasets, respectively. Minimum Origin Version Required: Origin 92 SR0

## Return

Returns the covariance between two datasets vx and vy.

## Example

newbook;
range aa = 1!1;
range bb = 1!2;
aa = uniform(32);
bb = uniform(32);
covariance = cov(aa,bb);
covariance = ;