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# fluxEddy

Calculates time averaged eddy flux quantities.

## Prototype

```	function fluxEddy (
x  : numeric,
y  : numeric
)

return_val  :  numeric
```

## Arguments

x

An array with one or more dimensions. The rightmost dimension must be time.

y

An array with one or more dimensions. It must have the same dimensions as x.

## Return value

An array of the same size as the input minus the rightmost dimension. Double if any input is double, float otherwise.

## Description

Calculates time averaged eddy flux quantities computed in one pass. Missing values are allowed.The approach used is:

```x=X+x'
y=Y+y'
```
where X and Y are time averages, then
```x'y' = ave{x*y} - X*Y.
```

## Examples

Example 1 Let x and y be 64 x 128 x 90

```    xpyp = fluxEddy(x,y)
;   xpyp = x'y' will be a 64 x 128 array
```
Example 2

Let u and v be four-dimensional with dimensions time, lev, lat, and lon. Reorder to make time the rightmost dimension.

```  upvp = fluxEddy(u(lev|:,lat|:,lon|:,time|:),v(lev|:,lat|:,lon|:,time|:))
; upvp will be three-dimensional with dimensions lev, lat, lon.
```
Example 3

Calculate the eddy variance of quantity z. (i.e. ave{z'z'}):

```    zpzp = fluxEddy(z,z)
```