how can I open multiple text file only specific low and then save??

I would like to open 18 txt. files at once only numbers except first three characters 1-3 row.

Also, I want to save these files row 1,501~16,500 only. How can I do this? I would appreciate if somebody help me.

[Jan]

I do not understand the question: "open 18 txt. files at once only numbers except first three characters 1-3 row" What does this mean?

[Houn JH]

I uploaded 18 trials of txt. files. These data contains 3 headers in 1-3 row.

Answer 1

[Akira Agata]

Like this? Running the following code at the directory where your data (*.txt) is stored, it extracts 1501~16500 rows and saves as a new data file (*b.txt).

fileList = dir('*.txt');

for kk = 1:numel(fileList)
  A = importdata(fileList(kk).name,'\t',3);
  data = A.data(1501:16500,:);
  [~,name,ext] = fileparts(fileList(kk).name);
  fileName = [name,'b',ext];
  dlmwrite(fileName,data,'precision',6);
end

[Houn JH]

Thanks a lot. It works really well. By the way, can I ask you about code?? I am trying to learn what you coded. These two lines can't understand what these functions are.. [~,name,ext] = fileparts(fileList(kk).name); fileName = [name,'b',ext];

Thanks!!

[Akira Agata]

Hi Houn-san,

Thank you for your response. The fileparts function returns file path, file name and file extension based on the input string. In this case, the input string fileList(kk).name contains only a file name and extension (e.g '01.txt'). So I have set the first output argument (=file path) as '~'. More details on fileparts function can be found here , but I would recommend try and see what happens by yourself, like:

>> [path,name,ext] = fileparts('01.txt')
path =
0×0 empty char array
name =
  '01'
ext =
  '.txt'

and

>> [path,name,ext] = fileparts('C:\folder\01.txt')
path =
  'C:\folder'
name =
  '01'
ext =
  '.txt'

And, in this case, [name,'b',ext] returns '01b.txt'.

[Houn JH]

Thanks. It really helpful for me.