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vhsgC

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

Prototype

	function vhsgC (
		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 vhagC function. These coefficients must be in mathematical coordinates. see:

http://www.scd.ucar.edu/css/software/spherepack/vhsgc.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

vhsgC performs the vector spherical harmonic syntheses using the coefficients in the multi-dimensional array bc generated by vhagC. Note that both vhagC and vhsgC operate on a gaussian 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 fixed grid, vhseC should be used. Also, note that vhsgC is the function version of vhsgc.

See Also

vhsgc, vhagC, vhagc, vhseC, vhsec, vhaec, vhaeC

Examples

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

Example 1

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

bc = vhagC (u,v)
     [do something with the coefficients]
UV = vhsgC (bc,nlon)	  
Example 2

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

bc = vhagC (u,v)
     [do something with the coefficients]
UV = vhsgC (bc,nlon) 	 
Example 3

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

bc = vhagC (u,v)
     [do something with the coefficients]
UV = vhsgC (bc,nlon)