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# vhseC

Computes vector spherical harmonic syntheses of vector fields on a fixed grid via spherical harmonics.

## Prototype

```	function vhseC (
bc    : numeric,
nlon  : byte, short, integer or long
)

return_val  :  float or double
```

## Arguments

bc

vector spherical harmonic coefficients (input). Under normal conditions the bc array was produced by the vhaeC function. These coefficients must be in mathematical coordinates. see:

http://www.scd.ucar.edu/css/software/spherepack/vhsec.txt

nlon

The size of the rightmost dimension of the original u and v arrays

As of version 6.0.0, this can be of type byte, short, integer or long.

## Return value

(For the arrays whose last two dimensions are nlat x nlon, the rest of the dimensions (if any) are collectively referred to as N. If the input/output arrays are just two dimensions, then N can either be considered equal to 1 or nothing at all.)

An array dimensioned 2 x N x nlat x nlon will be returned. The 0-th component of the leftmost dimension contains the reconstructed u array and the 1-th component of the leftmost dimension contains the reconstructed v array.

The return array will be double if the input array is double, otherwise it will be float.

## Description

vhseC performs the vector spherical harmonic syntheses using the coefficients in the multi-dimensional array bc generated by vhaeC. Note that both vhaeC and vhseC operate on a fixed grid.

NOTE: This function does not allow for missing data (defined by the _FillValue attribute) to be present.

If the original input arrays are on a gaussian grid, vhsgC should be used. Also, note that vhseC is the function version of vhsec.

## Examples

In the examples below, u and v are on a fixed grid.

Example 1

u(nlat,nlon), v(nlat,nlon)

```bc = vhaeC (u,v)
[do something with the coefficients]
UV = vhseC (bc,nlon)
```
Example 2

u(nt,nlat,nlon), v(nt,nlat,nlon)

```bc = vhaeC (u,v)
[do something with the coefficients]
UV = vhseC (bc,nlon)
```
Example 3

u(nt,nlvl,nlat,nlon), v(nt,nlvl,nlat,nlon)

```bc = vhaeC (u,v)
[do something with the coefficients]
UV = vhseC (bc,nlon)
```