NCINTERP is the jOceans module of jLab.

 NCINTERP  Interpolate field from NetCDF file onto specified positions.
 
    X=NCINTERP(FILENAME,NUM,LAT,LON,VARNAME) interpolates the field VARNAME
    from the NetCDF file FILENAME onto positions given by date numbers NUM,
    latitudes LAT, and longitudes LON, and returns the results in X.
 
    The interpolation is linear interpolation performed with INTERP3.
    Longitude boundaries and near-polar latitudes are both accommodated.
 
    The NetCDF file must a have a particular format.  The field VARNAME has
    three dimensions, latitude, longitude, and time, in that order.  The 
    file also has variables named 'lat', 'lon', and 'num' which give the 
    values along the dimensions.  Both lat and lon are oriented in order of
    increasing values.  The time NUM is given in Matlab's DATENUM format.   
 
    NCINTERP detects if longitude in FILENAME spans 360 degrees, and if so,
    interpolation across the longitudinal boundaries is correctly handled.
    Note that longitudes can be specified as [-180,180] or [0,360].
 
    NUM, LAT, and LON are all arrays of the same size, or else cell arrays
    of numeric arrays.  In the latter case, X will also be a cell array.
 
    [X1,X2,...,XN]=NCINTERP(FILENAME,NUM,LAT,LON,NAME1,NAME2,...,NAMEN),
    with multiple variable names input, also works, for example:
 
         [uwnd,vwnd]=ncinterp(filename,num,lat,lon,'uwnd','vwnd');
 
    FILENAME should specify a file on the Matlab search path, or should
    include the full pathname, e.g. FILENAME='/Volumes/Data/ncep_winds.nc'.  
 
    Failures in the interpolation, for example, if the data falls outside 
    the region covered by the NetCDF file, are set to values of INF.
    __________________________________________________________________
 
    Algorithms
   
    NCINTERP has two different approaches to reading the data.  The default
    behavior is to load in time chunks such that each double-precision 
    variable read in is smaller than a specified size, chosen as 16 GB.
 
    NCINTERP(...,M) instead uses M gigabytes as the cutoff for the chunk. 
    This method tends to be relatively fast.
 
    NCINTERP(...,'loop') alternatively reads each time slice invididually
    This method is very slow and is recommended only for testing purposes.
    __________________________________________________________________
 
    Handling domain edges
 
    If the NetCDF file spans 360 degrees of longitude, the first and last
    longitude are periodically wrapped to provide continuous interpolation.
 
    To prevent the interpolation from failing very near the poles, the
    first and last latitudes are also repeated, provided the last latitude
    is within one latitude spacing interval of the pole. 
    __________________________________________________________________
 
    Usage: x=ncinterp(filename,num,lat,lon,varname);
           [x1,x2]=ncinterp(filename,num,lat,lon,varname1,varname2);
    __________________________________________________________________
    This is part of JLAB --- type 'help jlab' for more information
    (C) 2016 J.M. Lilly --- type 'help jlab_license' for details

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