%  ISLICE  Extracts a vertical slice of a scalar variable 
%          along row I from a 4D ECOM NetCDF file. 
%
%  USAGE: [u,y,z,jd]=islice(cdf,var,time,i_index)
%    cdf = NetCDF file name (string) (e.g. 'ecomsi.cdf')
%    var = variable name (string) (e.g. 'salt' for salinity)
%    time = time step (integer) (e.g. 1 for 1st time step)
%    i_index = I index along which to take vertical slice
%
%    u = 2D array of the variable "var"
%    y = along slice coordinates (km)
%    z = depth coordinates (m)
%   jd = Julian time of slice (type "help julian" for details)
%
%
%   Example:  to extract temperature along I=20
%             from the 3rd time step in the file 'ecom3d.cdf', do:
%
%          [temp,x,y]=islice('ecom3d.cdf','temp',3,20);
%
%   Tip: Visualize these arrays using EXTCONTOUR,
%       [e.g. EXTCONTOUR(y,z,temp,'label','fill');]

% Rich Signell rsignell@usgs.gov