LONO) columns, onto locations (LAT,LON).
 
    Here LAT and LON are 2D arrays of the same size.  LATO and LONO should
    1D arrays such that ZO is plaid; otherwise see <a href="sphereinterp.html">SPHEREINTERP</a>.
 
    A difficulty in interpolating latitude and longitude is that longitude
    is periodic, for example, if LONO=0.5:1:359.5.  Then the interpolation
    can fail if 0<LON<0.5 or 359.5<LON<360.  <a href="interplatlon.html">INTERPLATLON</a> checks for LONO 
    being periodic, and if so it handl