Reading specific lines from multiple text files

Hi all,

I am only interested in the numerical values of line 10 and line 11 of multiple text files. Right now, i am using below code, but with %s, i get complete string and with %f, i donot get any values. Will really appreciate some helop

clear;

D = 'T:\New\files';
S = dir(fullfile(D, '*.txt'));
N = length(S);
for k = 1:N
  fid = fopen(fullfile(D,S(k).name), 'r');
  linenum = 10;
  h(k)= textscan(fid,'%s',1,'delimiter','\n', 'headerlines',linenum-1);
  fid=fclose(fid);
end

Answer 1

[dpb]

Ya' gotsa' skip the text to get to the floating point value...

...
T=cell2mat(textscan(fid,'%*s%f',1,'HeaderLines',linenum-1));
...

results in

>> T
T =
   180
>> 

[fadzhi]

Many thanks for your comment but i am running it over a loop for multiple text file but i getting an error

D = 'c:files';
S = dir(fullfile(D, '*.txt'));
N = length(S);
h = cell(N,1);
for k = 1:N
    fid = fopen(fullfile(D,S(k).name), 'r'); % open file
    linenum = 12;
    h(k) = cell2mat(textscan(fid, '%*s%f', 1, 'Headerlines', linenum-1));  
    fclose(fid);
end

[dpb]

...
h = zeros(N,1);     % cell2mat() returns double, not cell
for k = 1:N
    fid = fopen(fullfile(D,S(k).name), 'r'); % open file
    linenum = 12;
    h(k) = cell2mat(textscan(fid, '%*s%f', 1, 'Headerlines', linenum-1));  
    fclose(fid);
end

Also, you changed value of linenum which won't match with the sample file location for the tmperature record.

NB: the above will only retrieve a number from a record with a single text string before the floating point number;

Messlaenge Extensometer: 50.000 [mm] 

will fail.

> cell2mat(textscan(fid,'%*s%f %*[^\n]',inf,'Delimiter',':','HeaderLines',5))
ans =
   50.0000
   12.5000
    1.5000
    0.1000
  180.0000
    7.5000
       NaN
   72.2000
>> fid=fclose(fid);
>> 

returns the array beginning with Messlaenge Extensometer: 50.000 [mm]

Or, can return the leading string as well...

>> frewind(fid)
>> (textscan(fid,'%s%f %*[^\n]',inf,'Delimiter',':','HeaderLines',5))
ans =
  1×2 cell array
    {8×1 cell}    {8×1 double}
>> ans{:}
ans =
  8×1 cell array
    {'Messlaenge Extensometer'  }
    {'Probenbreite'             }
    {'Probendicke'              }
    {'Dehnrate'                 }
    {'Temperatur'               }
    {'Pruefgeschwindigkeit'     }
    {'Kennwerte(*1)'            }
    {'Elastizitaetsmodul E (*2)'}
ans =
   50.0000
   12.5000
    1.5000
    0.1000
  180.0000
    7.5000
       NaN
   72.2000
>>