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# ndtooned

Converts a multi-dimensional array to a one-dimensional array.

## Prototype

```	function ndtooned (
val
)

return_val [*] :  typeof(val)
```

## Arguments

val

An array of any dimensionality or type.

## Description

This function converts a multi-dimensional array to a one-dimensional array that has a length equal to product(dimsizes(val)).

## Examples

Example 1

```    a = (/(/1,2,3/),(/4,5,6/),(/7,8,9/)/)
b = ndtooned(a)
print(b)    ; should be (/1,2,3,4,5,6,7,8,9/)
```

Example 2

Consider x(ntim,nlat,mlon). Here the 'ntim' dumension contains monthly data for multiple years. Let's say that you want to create a new arrays that contain just January, February, March values.

```  nyears = ntim/12

x1d     = ndtooned(x)
x4d     = onedtond(x1d,(/nyears,12,nlat,nlon/))

; The above two lines can also be written as one line:
; x4d     = onedtond(ndtooned(x),(/nyears,12,nlat,nlon/))

x_jfm   = x4d(:,0:2,:,:)  ;  now subscript the second dimension for the desired months you want:
```
Further, lets say that the January, Feb, December are desired or March, July, October, November:

```   x_djf  = x4d(:,(/0,1,11/),:,:)
x_mjon = x4d(:,(/2,6,9,10/),:,:)
```