Spatial 2points averaging

[Enrique Sanchez <esanchez@xxxxxxxxxx>]

Hi all:
I have a very stupid problem to solve, I hope.
I have a field in a XY plane, of let's say
80x72 points. But I want to average it to
a 40x36 domain, just averaging every 2 points in both dimensions. How
can I do this?
Thanks a lot in advance,

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Dr. Enrique Sanchez Sanchez            esanchez@fis.ucm.es
Dpto. Geofisica y Meteorologia       Tel.- 34.91.394.44.40
Facultad Ciencias Fisicas            Fax.- 34.91.394.43.98
Universidad Complutense de Madrid (UCM)
Avda. Complutense s/n (28040)  Madrid (Spain)
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