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pdfxy_bin

Performs looping necessary to calculate the bivariate (joint) probability distribution (see pdfxy).

Available in version 5.1.1 and later.

Prototype

	procedure pdfxy_bin (
		x           : numeric ,  
		y           : numeric ,  
		binxbnd [*] : numeric ,  
		binybnd [*] : numeric ,  
		opt     [1] : logical    
	)

Arguments

x
y

Arrays of any dimensionality. The arrays must be the same size.

binxbnd
binybnd

One dimensional arrays containing the bin boundaries for the x and y arrays, respectively.

opt

If opt=False, then the PDF will be returned in units of percent (%). If opt=True and opt@fraction=True then the units will be 'fraction'.

Description

This function is designed to be called by pdfxy located in the "contributed.ncl" library. However, it can be called as a stand-alone function.

This function was added increase the efficiency of the multiple looping necessary to calculate the joint probability distribution function (PDF).

See Also

pdfxy, pdfx, bin_sum, bin_avg

Examples

Example 1

This function was meant to be invoked by pdfxy. However, it can be invoked directly. 

 
  x     = random_normal( 0,50, (/96,144/))
  y     = random_normal (40,25, dimsizes(x))

  binx  = fspan(-200,202,21)
  biny  = fspan( -50,144,19)

  pdf   = pdfxy_bin(x,y, binx,biny, False)
If the PDF is to have units of 'fraction', use 
  opt   = True
  opt@fraction = True
  pdf   = pdfxy_bin(x,y, binx,biny, opt)