get error when inputting data from csv file line by line;

Hello!

I tried to read a double-quoted csv file. This csv file was not in a good shape. It had multiple headers, blanks lines above the data part, so I have to do data input line by line.

CSV data looks like:

-------------------------------------------------------

"date:", "XX XX"

"Operator:", "XXXX"

" "

"XXXXXXXX", "XXXX", "YYYY", "NNNN"

"DataType", "NET"

"a", "b", "c", "d", .. "e"

"1", "2", "2", "3", .. "1"

"2", "2", "2", "3", .. "1"

"3", "3", "2", "3", .. "1"

"4", "2", "6", "3", .. "0"

"5", "2", "2", "3", .. "1"

...

" "

"other", "other"

...

----------------------------------------

My code starts reading data into variable 'NET' when the 1st column is a 'DataType' plus the 2nd colum is a 'NET'. (please see the following code).

variable 'NET' was set to [ ] by default (code: NET=[ ]). But when I use ( NET=[NET; line]; ), I got the following error:

??? Error using ==> vertcat

CAT arguments dimensions are not consistent .

I think I made mistakes in my code, but did not know how to fix it. Any help?

Thanks!!

 %code ------------------------------------------------;

 fid_t = fopen(...
    'C:datafile.csv', 'r');

 while ~feof(fid_t)
   temp1 = fgetl(fid_t); 
   temp2 = regexprep(temp1, '"', '');
   line = csv2cell(temp2);

   if strcmp(line{1}, 'DataType:')
       if strcmp(line{2}, 'Net')
           O2=line{2};
           fgetl(fid_t);

            NET=[];

           while ~feof(fid_t)
               tp1 = fgetl(fid_t);
               tp2 = regexprep(tp1, '"', '');
                line = csv2cell(tp2);     
               if isempty(line)
                  break;
               end
              NET=[NET; line];
           end

       end
   end
end;   
fclose(fid_t);

Answer 1

[Walter Roberson]

When you get near the bottom, "line" will not have as many fields, and you will be trying to vertcat() together two cell arrays with different number of columns.

Change

NET=[NET; line];

to

NET(end+1) = line;

and you will instead build up NET as a cell array row vector each element of which is a cell produced by csv2cell().

[Ken]

Walter, thanks for your quick reply. But when I used NET(end+1) = line; I got: ??? The following error occurred converting from cell to double: Error using ==> double Conversion to double from cell is not possible.

I am quite new to Matlab. Does this causes by using csv2cell()?

[Walter Roberson]

Initialize

NET = {};

[Ken]

Walter, after using NET={}; I got:

??? Subscripted assignment dimension mismatch.

I think I have trouble initializing 'cell'. Is it possible to initialize "NET={}" then use "NET(end+i)=line" to change NET's dimension repeatedly?

[Walter Roberson]

Yes, that should be okay, other than using end+1 instead of end+i. Provided, that is, that csv2cell() really does return a cell array.