MATLAB: Concatenation is missing values

Question

I am using the command:

doubArray = cat(1,cellStruct{:,3});

to extract an array of numeric values from a cell structure of mixed variable types. All of the variables in column 3 of the cell structure are of data type “double“.

The resulting array is missing 33 of the 116397 expected entires. The missing 33 entries are from a variety of locations within the cell structure and there does not appear to be any rhyme or reason behind which entries are missing.

Has anyone encountered this problem before and know of a solution?

Answer 1

33 of the cells in the third column contain empty arrays:

>> find(cellfun('isempty',cellStruct(:,3)))
ans =
   21968
   21969
   27848
   35808
   43424
   52648
   52649
   52650
   52651
   52652
   52653
   52654
   52655
   60284
   60285
   60286
   60287
   60288
   60289
   60290
   60291
   60292
   60293
   60294
   60295
   60296
   60297
   60298
   60299
   65762
   65763
   65839
   65840
  

While the rest of the cells in the third column apparently have one row:

>> find(cellfun('size',cellStruct(:,3),1)>1)
ans = []

In any case, the total number of rows in all of the cells in the third colum is:

>> sum(cellfun('size',cellStruct(:,3),1))
ans =  116364

And that is the exact number of rows that your numeric array contains:

>> size(doubArray,1)
ans =  116364

So far nothing suggests that any data has gone "missing" when concatenating those cell contents.