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NormCosWgtGlobe

Create normalized cosine weights that sum to 2.0.

Prototype

load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/contributed.ncl"  ; This library is automatically loaded
                                                             ; from NCL V6.2.0 onward.
                                                             ; No need for user to explicitly load.

	function NormCosWgtGlobe (
		lat [*] : numeric   
	)

	return_val [*] :  float

Arguments

lat

Latitudes of global grid [degrees].

Return value

A one-dimensional array of same size and type as lat.

Description

Generates cosine based weights that sum to 2.0. This is analogous to latGauWgt and latRegWgt.

See Also

latGauWgt, latRegWgt, latGau, latGlobeF, latGlobeFo, lonGlobeF, lonGlobeFo, gaus

Examples

The following require that contributed.ncl be loaded prior to invoking the function. 

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

Example 1

Consider a variable, lat, which is of type "double", and spans 87.5S to 87.5N [5 deg spacing]. 

  wgt  = NormCosWgtGlobe(lat)

  printVarSummary(wgt)
  print(lat+"    "+wgt)
  print("sum(wgt)="+sum(wgt))
The output looks like: 
Variable: wgt
Type: double
Total Size: 288 bytes
            36 values
Number of Dimensions: 1
Dimensions and sizes:   [lat | 36]
Coordinates:
            lat: [-87.5..87.5]
Number Of Attributes: 1
  long_name :   latitude weight

=======
         lat      wgt
(0)     -87.5   0.0038053
(1)     -82.5   0.0113869
(2)     -77.5   0.0188819
[snip]
(16)     -7.5   0.0864924
(17)     -2.5   0.0871557
(18)      2.5   0.0871557
(19)      7.5   0.0864924
[snip]
(33)     77.5   0.0188819
(34)     82.5   0.0113869
(35)     87.5   0.0038053
=======
(0)     sum(wgt)=2
Example 2

Consider a variable, lat, which is of type float, and spans 90S to 90N [5 deg spacing]. 

  wgt  = NormCosWgtGlobe(lat)

  printVarSummary(wgt)
  print(lat+"    "+wgt)
  print("sum(wgt)="+sum(wgt))
The edited output looks like: 
Variable: wgt
Type: float
Number of Dimensions: 1
Dimensions and sizes:   [lat | 37]
Coordinates:
            lat: [-90.0..90.0]
Number Of Attributes: 1
  long_name :   latitude weight

=======
         lat      wgt
(0)     -90   0.0
(1)     -85   0.0076106
(2)     -80   0.0151633
[snip]
(16)    -10   0.0859952
(17)     -5   0.0869896
(18)      0   0.0873219
(19)      5   0.0869896
(20)     10   0.0859952
[snip]
(34)     80   0.0151633
(35)     85   0.00761061
(36)     90   0.0
=======
(0)     sum(wgt)=2