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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 "$NCARG_ROOT/lib/ncarg/nclscripts/csm/gsn_code.ncl"
load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/gsn_csm.ncl"
load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/contributed.ncl"
load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/diagnostics_cam.ncl"

	function decompose2SymAsym (
		x        : numeric,  
		iret [1] : integer   
	)

	return_val  :  

Arguments

x

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

See Also

wkSpaceTime, wkSpaceTime_cam

Examples

See Example 10 of the Madden-Julian Oscillation web page.