常用程序

1. 数据结构

   % 设计数据结构
   years = 2003:2018;
   codg = struct('TEC', cell(numel(years), 1));
   for i = 1:numel(years)
      codg(i).TEC = nan(71, 73, 25, yeardays(years(i)));
   end
   
   % 重构数组
   % 四维转三维(71×73×24×365 -> 71×73×8760)
   tec = reshape(tec, 71, 73, []);
   % 三维转四维(71×73×8760 -> 71×73×24×365)
   tec = reshape(tec, 71, 73, 24, 365);
   % 高维转置(71×73×8760 -> 73×71×8760)
   tec = permute(tec, [2, 1, 3]);

2. 时间相关

   % 根据年月日计算年积日
   mdoy = doy(datetime(2021, 3, 21));  % mdoy = day(datetime(2021, 3, 21), 'dayofyear');
   % 根据年积日计算年月日
   ymd = datevec(datetime(2021, 1, 80));
   % 计算月份天数
   days = eomday(2021, 3);
   % 世界时转地方时
   dh = round(lon(j)/15);
   dmin = round((lon(j)/15-dh)*60);
   T = datevec(datetime(2021, 3, 21, ut+dh, 0+dmin, 0));

3. 构建网格点经纬度

   lon_1 = -180:5:180;
   lat_1 = 87.5:-2.5:-87.5;
   lon_2 = repelem((lon_1)', numel(lat_1));
   lat_2 = reshape(repmat((lat_1)', 1, numel(lon_1)), [], 1);

   

4. NetCDF文件

   读取文件

   file_path = fullfile(pwd, 'TEC.nc');
   % 读取变量
   lon = ncread(file_path, 'lon');
   lat = ncread(file_path, 'lat');
   tec = ncread(file_path, 'TEC')';  % 此处需要转置
   % 读取属性
   year = ncreadatt(file_path, '/', 'year');

   输出文件

   % 写入文件
   lon = -180:5:180;
   lat = 87.5:-2.5:-87.5;
   tec = zeros(numel(lat), numel(lon));
   name = 'TEC.nc';
   nc(lon, lat, tec, name);
   
   % 函数定义
   function nc(lon, lat, tec, name)
       cid = netcdf.create(name, 'NC_WRITE');
       dimidlon = netcdf.defDim(cid, 'lon', numel(lon));
       dimidlat = netcdf.defDim(cid, 'lat', numel(lat));
       varid1 = netcdf.defVar(cid, 'lon', 'double', dimidlon);
       varid2 = netcdf.defVar(cid, 'lat', 'double', dimidlat);
       varid3 = netcdf.defVar(cid, 'TEC', 'double', [dimidlon dimidlat]);
       netcdf.endDef(cid);
       netcdf.putVar(cid, varid1, lon);
       netcdf.putVar(cid, varid2, lat);
       netcdf.putVar(cid, varid3, tec');
       % netcdf.reDef(cid);
       % netcdf.putAtt(cid, netcdf.getConstant("NC_GLOBAL"), 'year', 2021);
       netcdf.close(cid);
   end

5. 创建保存目录

   dir_path = fullfile(pwd, num2str(years(i)));
   if ~exist(dir_path,'dir')
      mkdir(dir_path);
   end

6. 导出图片

   ax = gca;
   fg = gcf;
   set(ax, 'LineWidth', 1.0);
   set(fg, 'Units', 'centimeters','Position', [2, 2, 15, 8]);
   annotation('line', [ax.Position(1), ax.Position(1)+ax.Position(3)], [1, 1].*(ax.Position(2)+ax.Position(4)), 'LineStyle', '-', 'LineWidth', ax.LineWidth, 'Color', ax.XColor);
   annotation('line', [1, 1].*(ax.Position(1)+ax.Position(3)), [ax.Position(2), ax.Position(2)+ax.Position(4)], 'LineStyle', '-', 'LineWidth', ax.LineWidth, 'Color', ax.XColor);
   exportgraphics(gcf, 'Test_1.png', 'Resolution', 600);