write a matrix to a text file

I'd like to write a matrix into a text file, but I don't want elements with NaN value appear in the file, instead I want an empty space for each NaN value, here is a part of the matrix:

1. 1 NaN NaN NaN NaN
2. 3 4 4 NaN NaN
3. 6 1 NaN NaN NaN
4. 2 2 NaN NaN NaN
5. 4 4 5 NaN NaN
6. 6 2 3 2 NaN

thanks!

[Walter Roberson]

Are the NaN certain to be at the end of the line? If not then a different method would have to be used.

Answer 1

[Laura Proctor]

I wrote the following code which writes it line by line. Do you need the line breaks to be as they are in the original matrix? If not, then a FOR loop wouldn't be necessary.

A = [   1 NaN NaN NaN NaN
        3 4 4 NaN NaN
        6 1 NaN NaN NaN
        2 2 NaN NaN NaN
        4 4 5 NaN NaN
        6 2 3 2 NaN ]

fid = fopen('stuff.txt','w+');

for idx = 1:size(A,1)
    line = A(idx,~isnan(A(idx,:)));  % creates the line of data without NaNs
    fprintf(fid,[repmat('%d ',1,length(line)),'\n'],line);
end

fclose(fid);

[Arash]

thanks! could you please explain a little bit about "[" on the line: fprintf(fid,[repmat('%d ',1,length(line)),'\n'],line);

what exactly brackets do?

[Walter Roberson]

The [] are horizontal concatenation in this contexts. Building up a string by parts.