Does ncwrite work for multi-dimensional matrix?

I was trying to write a 3D matrix into the .nc file that I created with nccreate. The information dumped by ncdisp function indicated the file is properly created.

Here is the code I used to create and write the file.

nccreate('ERA5_2015_EVAm.nc','longitude','Dimensions',{'longitude',360},'Datatype','single','Format','64bit');

ncwriteatt('ERA5_2015_EVAm.nc','/','Conventions','CF-1.6');

ncwriteatt('ERA5_2015_EVAm.nc','longitude','units','degrees');

ncwriteatt('ERA5_2015_EVAm.nc','longitude','long_name','longitude');

nccreate('ERA5_2015_EVAm.nc','latitude','Dimensions',{'latitude',180},'Datatype','single');

ncwriteatt('ERA5_2015_EVAm.nc','latitude','units','degrees');

ncwriteatt('ERA5_2015_EVAm.nc','latitude','long_name','latitude');

nccreate('ERA5_2015_EVAm.nc','time','Dimensions',{'time',8760},'Datatype','int32');

ncwriteatt('ERA5_2015_EVAm.nc','time','units','hour since 1900-01-01 00:00:0.0');

ncwriteatt('ERA5_2015_EVAm.nc','time','long_name','time');

ncwriteatt('ERA5_2015_EVAm.nc','time','calendar','gregorian');

nccreate('ERA5_2015_EVAm.nc','e','Dimensions',{'longitude',360,'latitude',180,'time',8760},'Datatype','int16');

ncwriteatt('ERA5_2015_EVAm.nc','e','units','m of water equivalent');

ncwriteatt('ERA5_2015_EVAm.nc','e','long_name','Evaporation');

ncwriteatt('ERA5_2015_EVAm.nc','e','standard_name','lwe_thickness_of_water_evaporation_amount');

time = ncread('ERA5_2015_EVA.nc','time');

longitude = double(ncread('ERA5_2015_EVA.nc','longitude'));

lon(1:180,1) = longitude(181:360)-360;
lon(181:360,1) = longitude(1:180);
lon(361,1) = 180;
lat = double(ncread('ERA5_2015_EVA.nc','latitude'));

e = double(ncread('ERA5_2015_EVA.nc','e'));

eva(1:180,:,:) = e(181:360,:,:);eva(181:360,:,:) = e(1:180,:,:);eva(361,:,:) = e(181,:,:);

clear e;

[x0,y0] = meshgrid(lon,lat);

[x,y] = meshgrid(-179.5:179.5,-89.5:89.5);

for i = 1:8760

      e(1:360,1:180,i) = interp2(x0,y0,eva(:,:,i)',x,y,'nearest')';

end

clear eva;

ncwrite('ERA5_2015_EVAm.nc','longitude',-179.5:179.5);

ncwrite('ERA5_2015_EVAm.nc','latitude',-89.5:89.5);

for Ilon = 1:360

      for Ilat = 1:180

          ncwrite('ERA5_2015_EVAm.nc','e',e(Ilon,Ilat,:),[Ilon Ilat 1]);

      end
  end

ncwrite('ERA5_2015_EVAm.nc','time',time);

The longitude, latitude and time has been properly input into the file while the 'e' is not. The 'e' I read from the .nc file after writing is zero at all grids as indicated below,

e = double(ncread('ERA5_2015_EVAm.nc','e'));  
figure;pcolor(e(:,:,1));shading interp;

while the actual distribution of 'e' should be like this,

      figure;pcolor(e(:,:,1));shading interp;

I am sure I did something stupidly wrong, hoping for suggestion from the community!

Many thanks!

Shenjie

[Jan]

Please improve the readability of your code: https://www.mathworks.com/matlabcentral/answers/13205-tutorial-how-to-format-your-question-with-markup

[Shenjie Zhou]

Hi Jan, sorry about the annoying format, I've made some modification of the code, hope it should be easy to read now. Cheers