Average based on logical mask and condition

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nlm 2018-11-5

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评论： nlm 2018-11-6

I want to average the data according to unique ID and a logical mask. I have 3 km logical mask which will average into perfect 36 km grid. I average into 36 km based on compartmentID I created. I'm having trouble, when I want to discard those 36 km grids when one of the 3 km grid is zero (based on logical mask ID). Size of the matrix is 406, 964 for 36 km grid which perfectly fit 4872, 11568 3 km grids.

%Form the ID's for 3 km grid so to average for 36 km grid. 
rowId = ceil( (1 : 4872) / 12 ); 
colId = ceil( (1 : 11568) / 12 );
[colID, rowID] = meshgrid( colId, rowId );
compartmentID = colID + (rowID - 1) * max(colId);
Average = reshape(accumarray(compartmentID(:),reshape(Grid_3km,[],1), [],@mean,NaN ), 406, 964);

Can anyone help me with the condition, that says if one of the 3 km grid in 36 km is zero then discard the average.

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nlm 2018-11-6

编辑：nlm 2018-11-6

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Please find the mat file attached. I need to remove all the compartment ID numbers of 36 km grid even if one of the 3 km grid within 36 km is zero. This is my code. Since there are 144 perfect 3 km grid in a 36 km grid, I wrote this code, it works but very slowly. more than 10 hrs and hasn't finished even one matrix. Unable to attach the file. It is a 4872 by 11568 matrix, it is 12 Mb after zip too. Any idea how I can attach the file? I attached picture of 1) perfect 36 km grid, where repeated numbers represent 3 km grids, 2) imperfect 36 km grid, where zero's indicate missing 3 km grid. I want to remove all the 36 km grids where even one of the 3 km is zero.

Any help is highly appreciated !!!!

 x = unique(New_IMERG(1).compartment);
  parfor ii=1:size(New_IMERG,1)
         for jj=1:size(x,1)
      A = sum(New_IMERG(ii).compartment == x(jj),1);
          f sum(A) < 144
             New_IMERG(ii).compartmentNEW(New_IMERG(ii).compartment==x(jj)) = 0; 
         end 
        end 
  end

nlm 2018-11-6

Sorry, I could not attach it. It was larger than 5 Mb.

nlm 2018-11-6

@JohnGalt Can you please elaborate ?

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Bruno Luong 2018-11-6

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Just put NaN on the 3km-grid at the place you want to discard

Grid_3km_Masked = Grid_3km;
Grid_3km_Masked(YourMask==0) = NaN;

then by using your working code on Grid_3km_Masked, it will propagate to the average on coarse-grid data result:

%Form the ID's for 3 km grid so to average for 36 km grid. 
rowId = ceil( (1 : 4872) / 12 ); 
colId = ceil( (1 : 11568) / 12 );
[colID, rowID] = meshgrid( colId, rowId );
compartmentID = colID + (rowID - 1) * max(colId);
Average = reshape(accumarray(compartmentID(:),reshape(Grid_3km_Masked,[],1), [],@mean,NaN ), 406, 964);