delete.m

来自「MATLAB中读写、处理科学数据文件格式NETCDF的程序」· M 代码 · 共 134 行

function theResult = delete(self, varargin)

% netcdf/delete -- Delete items from NetCDF file.
%  delete(self, item1, item2, ...) deletes the given items
%   ("ncdim", "ncvar", or "ncatt" objects) from the NetCDF
%   file represented by self, a "netcdf" object.  The
%   updated "netcdf" object is returned.
 
% Copyright (C) 1997 Dr. Charles R. Denham, ZYDECO.
%  All Rights Reserved.
%   Disclosure without explicit written consent from the
%    copyright owner does not constitute publication.
 
% Version of 13-Aug-1997 08:51:21.
% Updated    12-Nov-2002 14:41:20.

result = [];
if nargout > 0, theResult = result; end

if nargin < 2, help(mfilename), return, end

self = ncregister(self);

theItems = varargin;
if length(varargin) < 1, return, end

switch permission(self)
case 'nowrite'
   disp([' ## No "' mfilename '" action taken; ' ...
              'file "' name(self) '" permission is "nowrite".'])
   return
otherwise
end

% All objects.

theObjects = [att(self) dim(self) var(self)];

% Cull items to be deleted.

for i = 1:length(theItems)
   for k = length(theObjects):-1:1
      if isequal(theObjects{k}, theItems{i})
         theObjects(k) = [];
      end
   end
end

% Temporary file.

temp = netcdf('random');
if isempty(temp), return, end

% Copy dimensions and global attributes.

for k = 1:length(theObjects)
   switch ncclass(theObjects{k})
   case 'ncdim'
      d = theObjects{k};
      copy(d, temp)
   case 'ncatt'
      g = theObjects{k};
      if isglobal(g), copy(g, temp), end
   otherwise
   end
end

% Copy variable definitions and attributes.

for k = 1:length(theObjects)
   switch ncclass(theObjects{k})
   case 'ncvar'
      v = theObjects{k};
      copy(v, temp, 0, 0, 0)
      a = att(v);
      for j = length(a):-1:1
         for i = 1:length(theItems)
            if isequal(a{j}, theItems{i}), a(j) = []; end
         end
      end
      
% Matlab 6.5 is acting odd with respect to "subsref/subsasgn".
%  It seems to forget or ignore the fact that some variables
%  are objects, not doubles or cells.  For example, the
%  following "u = temp{name(v)}" generates an error, saying
%  that "{...}" refers to a cell where no cell exists --
%  indeed, "temp" is a "netcdf" object, which has its
%  own "{...}" non-cell syntax.  Evidently, Matlab would
%  prefer that we not use "(){}." syntax within the body
%  of methods of the same class.  But what about derived
%  classes?

if (0)
	hello
	temp
	class(temp)
	name(v)
	u = temp{name(v)};
end

      u = ncvar(name(v), temp);   % Revised from above.
      
      for j = 1:length(a), copy(a{j}, u), end
   end
end

% Copy variable data.

for k = 1:length(theObjects)
   switch ncclass(theObjects{k})
   case 'ncvar'
      v = theObjects{k};
      copy(v, temp, 1, 0, 0)
   otherwise
   end
end

theTempFilename = name(temp);
theFilename = name(self);

close(temp)
close(self)

fcopy(theTempFilename, theFilename)
delete(theTempFilename)

result = netcdf(theFilename, 'write');

if nargout > 0
   theResult = result;
else
   ncans(result)
end