Is it possible to use two textscan statements in a row ?

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Hello,
I am trying to extract some data from a text file.
My text file contains several lines written this way:
I want to extract the parameters after the colons.
Here's my code :
It is supposed to return me C1 = "Mars 2022" and C2 = "16:17:50".
I get the following error message :
It seems like I cannot use two textscan statements in a row. In the workspace, C1 = "Mars 2022" but C2 is an empty cell.
Two additional questions :
  • how to handle the empty string after 'nom' ? I would like that C3 = "".
  • 'affaire' has multiple occurences within my textfile, but I'm only interested in the first one. How to do so ?
Any help would be greatly appreciated,
Gwendal
  2 Comments
Stephen23
Stephen23 on 28 Mar 2022
@Gwendal Marrec: please upload a sample file by clicking the paperclip button.
Gwendal Marrec
Gwendal Marrec on 28 Mar 2022
I've uploaded a copy of the text file I'm working on as well as the lines of code I'm trying to use.

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Accepted Answer

Stephen23
Stephen23 on 28 Mar 2022
Edited: Stephen23 on 28 Mar 2022
"Is it possible to use two textscan statements in a row ?"
Yes, you can call TEXTSCAN as many times as you want on one file, I have often used this to read blocks of data separated by intermediate "header" lines. Quite handy, but probably not the best approach for your data file.
str = fileread('textscan_error.txt');
tmp = regexpi(str,'(?<=INFORMATION\s*\{\s*)[^\}]+','once','match');
tkn = regexp(tmp,'(\w+)\s*:\s*"([^"]*)','tokens');
tkn = vertcat(tkn{:}).';
out = struct(tkn{:})
out = struct with fields:
date: 'Mars 2022' heure: '16:17:50' nom: '' affaire: 'stage' protection: '_'
out.heure
ans = '16:17:50'
out.affaire
ans = 'stage'
If you really want to use TEXTSCAN:
opt = {};
fmt = '%s:%q';
[fid,msg] = fopen('textscan_error.txt','rt');
assert(fid>0,msg)
str = 'X';
while ~startsWith(str,'INFORMATION')
str = fgetl(fid);
end
tmp = textscan(fid,fmt,opt{:});
fclose(fid);
tmp{:}
ans = 6×1 cell array
{'date' } {'heure' } {'nom' } {'affaire' } {'protection'} {'}' }
ans = 5×1 cell array
{'Mars 2022'} {'16:17:50' } {0×0 char } {'stage' } {'_' }
  1 Comment
Gwendal Marrec
Gwendal Marrec on 30 Mar 2022
Thank you very much ! Your first solution helped me a lot, I've modified it a bit so now it fits perfectly to my real datafile.
Have a nice day,
Gwendal

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