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dsgrid2d

Interpolates double data from an unstructured (randomly-spaced) grid to a rectilinear grid using inverse distance weighted interpolation. (Deprecated version.)

Prototype

	function dsgrid2d (
		x  [*] : double,  
		y  [*] : double,  
		z      : double,  
		xo [*] : double,  
		yo [*] : double   
	)

	return_val  :  double

Arguments

x

A 1D array of length (npts) containing the X coordinates of the input data.

y

A 1D array of length (npts) containing the Y coordinates of the input data.

z

An array of any dimensionality (last dimension must be npts) containing the functional values of the input data. Element z(...,i) is the value of the input function at coordinate (x(i), y(i)) for i = 0, npts - 1).

xo

A 1D array of any length (numxout) containing the X coordinates of the output data grid. The values in xo must be increasing, but need not be equally spaced.

yo

A 1D array of any length (numyout) containing the Y coordinates of the output data grid. The values in yo must be increasing, but need not be equally spaced.

Return value

Returns a double array dimensioned as N x numxout x numyout, where N represents all but the last dimension of z.

Description

[Deprecated: use dsgrid2 instead.]

This function performs interpolation from double data on an unstructured grid to data on a rectilinear grid. This function requires that desired values for control parameters have been set using the procedure dssetp.

This function is part of the Dsgrid package which implements a simple inverse distance weighted interpolation algorithm. No missing values are allowed.

See Also

dsgrid2 dsgrid3 dspnt2 dspnt3 dsgetp dssetp

Examples

begin

  NUM = 6
  NX = 61
  NY = 61

  xi = (/0.00, 1.00, 0.00, 1.00, 0.40, 0.75/)
  yi = (/0.00, 0.00, 1.00, 1.00, 0.20, 0.65/)
  zi = (/0.00, 0.00, 0.00, 0.00, 1.25, 0.80/)
  xeye =  3.3
  yeye = -3.3
  zeye =  3.3

  xo = new((/NX/), double)
  yo = new((/NY/), double)

;
; Create the output grid.
;
  xinc = 1.0 / (NX - 1) 
  yinc = 1.0 / (NY - 1) 
  ii = fspan(0.0, 60.0, NX)
  xo = xinc * ii
  yo = yinc * ii
;
; Exponent equals 0.5
;
  dssetp("exp", 0.5)
  zo = dsgrid2d(xi, yi, zi, xo, yo)
end