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# dim_min_n

Finds the minimum of a variable's given dimensions at all other dimensions.

## Prototype

```	function dim_min_n (
x        : numeric,
dims [*] : integer
)

return_val  :  typeof(x)
```

## Arguments

x

A variable of numeric type and any dimensionality.

dims

The dimension(s) of x on which to take the minimum. Must be consecutive and monotonically increasing.

## Return value

The output dimensionality will be the same as all but dims's dimensions of the input variable. The dimension rank of the input variable will be reduced by the rank of dims.

## Description

The dim_min_n function determines the minimum of all elements in the dimensions indicated by dims for each index of the remaining dimensions. Missing values are ignored.

Use the dim_min_n_Wrap function if metadata retention is desired. The interface is identical.

## Examples

Example 1

Create a variable (q) of size (3,5,10) array. Then determine the minimum of the rightmost dimension.

```    q    = random_uniform(-20,100,(/3,5,10/))
qmin = dim_min_n(q,2)   ;==>  qmin(3,5)

; Use dim_min_n_Wrap if metadata retention is desired
qmin = dim_min_n_Wrap(q,2)   ;==>  qmin(3,5)
```
Note: when operating across the rightmost dimension, it is simpler to use dim_min.

Example 2

Let x be of size (ntim,nlat,mlon) and with named dimensions "time", "lat" and "lon", respectively. Then, for each time and latitude, the minimum longitude value may be obtained via:

```    xMinLon = dim_min_n( x, 2 )    ; ==> xMinLon(ntim,nlat)

; Use dim_min_n_Wrap if metadata retention is desired
; xMinLon = dim_min_n_Wrap( x, 2 )    ; ==> xMinLon(ntim,nlat)
```
Example 3

Let x be defined as in Example 2: x(time,lat,lon). Determine the minimum value over all time at each latitude/longitude grid point.

```    xMinTime = dim_min_n( x, 0 )    ; ==> xMinTime(nlat,nlon)

; Use dim_min_n_Wrap if metadata retention is desired
; xMinTime = dim_min_n_Wrap( x, 0 )    ; ==> xMinTime(nlat,nlon)
```
Example 4

Let x be x(time,lev,lat,lon). Determine the minimum value over all time/level values at each latitude/longitude grid point.

```    xMin = dim_min_n( x, (/0,1/))  ; ==> xMin(nlat,nlon)

; Use dim_min_n_Wrap if metadata retention is desired
; xMin = dim_min_n_Wrap( x, (/0,1/))  ; ==> xMin(nlat,nlon)
```