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wgt_area_smooth

Smooths an array of data using a 5-point 2D area-weighted smoothing algorithm.

Available in version 6.1.0 and later.

Prototype

	function wgt_area_smooth (
		field      : numeric,  
		wgt [*][*] : numeric,  
		opt    [1] : logical   
	)

	return_val [dimsizes(field)] :  float or double

Arguments

field

An array of 2 or more dimensions to be smoothed using a 5-point smoothing algorithm with area weighting. The 2 rightmost dimension sizes must match those of the 2D array of area weights.

wgt

A 2D array of area weights.

opt

A scalar logical value. If False, all attributes take their default value. If True, the following attribute is supported:

cyclic
When set True, the first and last elements of the rightmost dimension of the field variable are considered to be adjacent to each other, and can therefore be smoothed relative to each other. Otherwise, the first and last elements of the rightmost dimension of the output variable are set to the fill value. Defaults to True.

Return value

The return type is double if the input is double, and float otherwise.

Description

This function returns a smoothed array with the same dimensionality as the input field array. For each data value (j,i), the smoothed value is computed as a weighted average of the five points (j-1,i), (j,i), (j+1,i), (j,i-1), and (j,i+1).

See Also

smth9, smth9_Wrap