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decomposeSymAsym

Decompose a variable which is symmetric about the equator into symmetric and asymmetric parts.

Available in version 5.1.0 and later.

Prototype

load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/gsn_code.ncl"        ; These three libraries are automatically
load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/gsn_csm.ncl"         ; loaded from NCL V6.2.0 onward.
load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/contributed.ncl"     ; No need for user to explicitly load.

load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/diagnostics_cam.ncl" ; Still need to load this library.

	function decomposeSymAsym (
		x        : numeric,  
		iret [1] : integer   
	)

	return_val  :  typeof(x)

Arguments

An array of at least two dimensions. Nominally, ([...,]lat,lon).

iret

Flag: iret=0 will return the decomposition in the original dimension order; iret=1 will return the decomposition with the dimension ordering permutated.

Return value

The return array will be the same type and rank as x. The dimension order may be changed depending upon iret.

Description

Nominally, the input x is partitioned as follows:

  antisymmetric part is stored in one hemisphere [eg: Northern Hemisphere]
           xOut( lat) = (x(lat)-x(-lat))/2
  symmetric part is stored in other hemisphere   [eg: Southern Hemisphere]
           xOut(-lat) = (x(lat)+x(-lat))/2

Examples