% Purpose
%    writes spacial axis value to data file.
%
% Synopsis
%    mexeps('putaxis',varcode,axid,axcode,name,frmt,units,type,ax_val)
%    mexeps('putaxis',varcode,axid,axcode,name,frmt,units,type,ax_val,range)
%
% Description
%    It sets and writes out spacial axis value to data file. The variable
%    which the axis associated with is refered to by variable code, 
%    varcode.  The axis is refered to by a axis id number, axid: 1 for
%    x-axis, 2 for y-axis, 3 for z-axis; and by the axis code, axcode
%    (e.g. 500 for latitude, 502 for longitude).  Input argument also
%    include axis name, format, units, type ('even' or 'uneven') and 
%    axis value (ax_val).  The last argument, range, is optional. When
%    it is not specified, all axis value will be written out; when it
%    is specified, it is a 1x2 array contains [lower upper] limits of
%    the axis value you want to write.  The data type of axis value 
%    written to netCDF file is float.
%
% Examples
%    Open a data file and write out spacial axis values.
%
%      mexeps('openw','pointer.file');       % open pointer file
%      mexeps('setnextw','datafile.ctd');    % open data file
%
%      lon = 156+0.2/60;  		%East
%      lat = 0.5/60;      		%North
%      depth = [0; 5; 10; 15; 20];      %depth
%      varcode = 20       		%temperature 
%
%      mexeps('putaxis',varcode,1,502,'lon',' ','degree_east','even',lon);
%      mexeps('putaxis',varcode,2,500,'lat',' ','degree_north','even',lat);
%      mexeps('putaxis',varcode,3,3,'depth',' ','m','even',depth);
%      ...
%	% write time axis
%	% write variable value
%      ...
%
% See Also
%    putvar, puttaxis
%