how can I append this format using dlmwrite ?

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Eliza
Eliza on 9 Feb 2018
Commented: Walter Roberson on 12 Feb 2018
I wanna the result in the text file to be
1 2 4 A
5 6 7 B
8 9 0 C
I used this formula but the result is not what I want
A=[1 2 4;5 6 7;8 9 0] B=[A;B;C]
dlmwrite('DECALLFEATURES.csv',A,'-append', 'newline', 'pc');
dlmwrite('DECALLFEATURES.csv',B,'delimiter','','-append','newline', 'pc');

Answers (1)

Walter Roberson
Walter Roberson on 9 Feb 2018
dlmwrite() cannot be used to output a mix of text and numeric on the same call.
dlmwrite() does not like to output text at all. You can trick it into handling text by setting the Delimiter property to empty, and set 'precision' to '%s', and pass in a character array with one row per line in which each row is the same length and contains all necessary characters including commas where you want to put the cell boundaries. dlmwrite() is not able to handle cell arrays.
dlmwrite() never appends to the end of an existing line. The -append flag causes it to add new data after all existing lines. The 'coffset' specification causes it to overwrite the file (unless -append was used) putting that many empty columns before the new data it writes.
I recommend you give up on using dlmwrite for this purpose.
You could switch to fopen/fprintf
A=[1 2 4;5 6 7;8 9 0]; B={'A';'B';'C'};
fid = fopen('DECALLFEATURES.csv', 'wt');
data_cell = [num2cell(A), B] .'; %transpose is important
fmt = [repmat('%d ', 1, size(A,2)), '%s\n'];
fprintf(fid, fmt, data_cell{:});
fclose(fid);
I do have to wonder why you are using a .csv file when you only have a single cell per line? csv does not interpret blanks as indicating the end of cells, so you are not creating a csv with 3 x 4 data, you are creating a csv with 3 x 1 data. csv expect commas to delimit cells.
  10 Comments
Eliza
Eliza on 12 Feb 2018
whos table
Name Size Bytes Class Attributes
table 4x6 2860 cell
>>
whos name
Name Size Bytes Class Attributes
name 1x4 8 char
>> whos reshapedfea
Name Size Bytes Class Attributes
reshapedfea 1x21 168 double
Walter Roberson
Walter Roberson on 12 Feb 2018
You assigned a cell array to the variable name table but the code I gave needs to use the function named table.

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