forms 2D or 3D interpolation appropriate for latitude
    and longitude.  It deals with issues arising from the periodicity of 
    longitude in addition to performing several other convenient functions. 
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    2D Interpolation
 
    Z=<a href="interplatlon.html">INTERPLATLON</a>(LATO,LONO,[],ZO,LAT,LON) performs a 2D interpolation
    from the array ZO, which has latitude varying in LENGTH(LATO) rows and
    longitude varying in LENGTH(