Copy with Matlab

Hi everyone!

I have this problem: I have a big data list in .txt file, with three columns and various lines; a variable number of lines constitutes a series. At the end of each series, there is a blank line. Then another series starts.

i.e.

20 23 103

98 23 92

22 11 118

19 32 110

(blank line)

15 15 22

11 33 33

55 55 55

98 22 22

(blank line)

43 44 23

33 33 44

40 33 99

12 23 43

...and so on. I would like to copy each series near the previous series. The copy of each series should end when it reaches the blank line.

i.e.

20 23 103 15 15 22 43 44 23

98 23 92 11 33 33 33 33 44

22 11 118 55 55 55 40 39 99

19 32 110 98 22 22 12 23 43

I have a Macro doing this in Excel and I can post it if you want, but I would like to do it in Matlab. Any idea? Thank you,

Ale

[Walter Roberson]

Are the series always equal length?

[Alessandro Innocenti]

No, they aren't. Or better, I have many .txt files: in the same file .txt all series are always equal lenght, but different .txt files have series that are different lenght.

Answer 1

[Macko]

Hi,

I'd probably be writting a Perl script that I then execute either on its own or from within the Matlab environment. I think the systax from within Matlab would be !!your_perl_script.pl.The Perl script would than parse the file and reformt it.

The reason I'd go for Perl in this case is because it has some very powerful string handling features (think regular expressions).

Hope this helps!

[Alessandro Innocenti]

I'm sorry, I didn't understand. Have you written the Perl Script yet? Or have you been writting?

Where could I find this script? How can I use it (I don't know what a Perl Script is)?

Thank you very much for your help.

Answer 2

[Alessandro Innocenti]

I'm sorry for my craving, but I really need help. Any idea? Thank you very much! Ale

Answer 3

[Christoph]

Well,

I'm not used to reading .txt files in Matlab, but there is a way I guess. I would read the entire file as one string and replace two newline commands with a temporary string. Next step is deleting the newline which are left. Final step is replacing the temporary string with one newline.

I know there might be better solutions, but this one should be pretty easy to implement. Just start reading the documentation files to this functions: - regexprep - fscanf

good luck, CN

Answer 4

[Walter Roberson]

inlines = {};
fid = fopen('YourFile.txt', 'r');
while true
  K = 0;
  thisline = fgetl(fid);
  if ~ischar(thisline); break; end   %end of file
  if length(deblank(thisline)) == 0; continue; end; %end of this series
  K = K + 1;
  if length(inlines) < K; inlines{K} = []; end
  inlines{K} = [inlines{K} fscanf('%f', thisline)];
end
fclose(fid);

seriesdata = cell2mat(inlines);

[Alessandro Innocenti]

I am sorry Walter but your solution doesn't work. When I run the script the answer is:

??? Error using ==> fscanf Invalid file identifier. Use fopen to generate a valid file identifier.

Error in ==> prova at 16 inlines{K} = [inlines{K} fscanf('%f', thisline)];

Is it possible that it doesn't work because I've an old version of Matlab (I have version R2008.b)? In this case do you know how can i change the script, to adapt it to my version of Matlab? Thank you. Ale

[Image Analyst]

It should be sscanf() instead of fscanf()

[Alessandro Innocenti]

Ok, if I change fscanf with sscanf the program runs...but I've now another problem. The program runs but...where can I see the results? As I have written before,I would like to copy each series near the previous series in a new file, but the program doesn't show me this result. Indeed, "inlines" is empty.

Thank you for your help! Ale

[Alessandro Innocenti]

Why the "inlines" matrix is empty?