error in attached program

Error using reshape
To RESHAPE the number of elements must not change.
Error in build_db (line 57)
     reduced_testdata = reshape(reduced_testdata, 24, 60)
%%Training images
  id_test = 0;
  id_train = 0;
   for folder_idx = 1 : 20            % no of classes
   for i = 1 : 9                             % no of images per class
   thisfile = fullfile('train', num2str(folder_idx), [num2str(i) '.bmp ']); 
   B = imread(thisfile ); 
   X = double(B);
    X = imresize(X,[120 120],'bilinear');  %300 250
       id_train = id_train+1;
       traindata{id_train}=ext_vein(X,1);
   end 
   end
%%Testing images
d=[];
for folder_idx = 1 : 20     %no of classes
 for i = 1 : 3                     % no of images per class
   thisfile = fullfile('test', num2str(folder_idx), [num2str(i) '.bmp ']); 
   B = imread(thisfile ); 
    X = double(B);
    X = imresize(X,[120 120],'bilinear');  %300 250
    id_test = id_test+1;
    testdata{id_test}=ext_vein(X,1);          
   end 
  end
   %%Reduced dimension of rows ( fixed to only 20 rows)
reduced_testdata = cellfun(@(M) M(1:min(end,4), :), testdata, 'uniform', 0);
reduced_traindata = cellfun(@(M) M(1:min(end,4), :), traindata, 'uniform', 0);
      %%reshape
       % reduced_testdata = reshape(reduced_testdata,1,[]);    
       reduced_testdata = reshape(reduced_testdata, 60,24);
       reduced_traindata = reshape(reduced_traindata, 180,24);
       %reduced_traindata =  reshape(reduced_traindata,1,[]);
save('db1.mat','reduced_testdata');
save('db2.mat','reduced_traindata');