text file dlmwrite fprintf save

Hi,

It might be another question on this subject.. but i'm confused saving text files.

i have a basic code with data(2,49) to save in each loop the data minus one row

 i=length(data)
 for j=1:i
 coord=[data(1:(i-j),1),data(1:(i-j),2)];

 filename = [ 'coord' num2str(j-i) '.txt' ];

Then I'm stuck..

 dlmwrite (filename, coord,'delimiter','\t','precision',7)

 end

do not write in column, I understood that text files are row oriented, but i don't get the fprintf way..

if someone can explain me..

Answer 1

[Walter Roberson]

You are not using fprintf() directly anywhere.

Anyhow, try

   dlmwrite (filename, transpose(coord),'delimiter','\t','precision',7)

By the way: your coord matrix is not 2 x 49: it is 49 x 2.

Also, you can abbreviate your creation of coord:

coord = data(1:i-j,1:2);

[Nicolas]

thanks, I put fprintf() because I saw some answers written using it. Thanks for the abbreviation hint! but transpose don't work. When i open the text file the data are still on a row.

Answer 2

[Oleg Komarov]

The version with fprintf:

% Sample data

data   = rand(49,2);
szData = size(data);

% Generate all filenames at once

filename = reshape(sprintf('coord-%02d.txt', szData(1)-1:-1:0),12,49).';

% Loop and use fprintf

for n = 1:szData(1)
    coord = data(1:szData(1)-n,:);
    fid   = fopen(filename(n,:),'w');
    fprintf(fid,'%.7f\t%.7f\r\n',coord.');
    fid   = fclose(fid);
end

[Nicolas]

??? Error using ==> reshape

To RESHAPE the number of elements must not change.

Error in ==> Generate_sequence at 6

filename = reshape(sprintf('Beb-coord-%02d.txt', szData(1)-1:-1:0),12,49).';

[Oleg Komarov]

You have to replace the 12 by the length of the name:

Beb-coord-48.txt, i.e. 16 chars.

filename = reshape(sprintf('Beb-coord-%02d.txt', szData(1)-1:-1:0),16,49).';