To eliminate the lines begin with "%"

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aneps
aneps on 25 Nov 2013
Answered: Image Analyst on 26 Nov 2013
I have a file (attached here) which I need to eliminate all the lines begin with "%" and remove the "commas" after the numbers. Then read the numbers and put in separate columns X, Y and Z. Can anyone help me to make the program?
  2 Comments
Walter Roberson
Walter Roberson on 25 Nov 2013
The file did not get attached.
aneps
aneps on 25 Nov 2013
Thank you... Now the file is attached

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Accepted Answer

Simon
Simon on 25 Nov 2013
Hi!
Read in your file:
% read in a file
fid = fopen(FileName);
FC = textscan(fid, '%s', 'delimiter', '\n');
fclose(fid);
FC = FC{1};
You can get rid of all "%" lines if you compare the first char like:
FC = FC(~strncmp('%', FC, 1));
You can get rid of all ',' with a regex like:
FC = regexprep(FC, ',', '');
Afterwards you can parse your cell array FC line-by-line with sscanf to extract numbers.
  3 Comments
aneps
aneps on 26 Nov 2013
This seems not working! As the file is bigger, I have uploaded in "transfer big files.com"(https://www.transferbigfiles.com/dd8e3ef1-95c6-4fd8-a00e-908d2a0706d8/a8MGzUPeLZXl-HV0oJ-nMg2). The file name is VMIVolt.asc.
Here, when I run this program, the final data "A" is seems somehow messed up! I couldn't understand what has happened! If I manually delete all the lines in the data begin with "%" and compare with the one I got by running the program above doesn't seems to match. For example, all the elements in the third column in the original data are zeros but after running the above program, the zeros are replaced with some numbers! Thanks a lot.
Simon
Simon on 26 Nov 2013
Hi!
It seems that sscanf fails for some reasons I don't know. But you can as well use
% use sscanf for each cell
A = cellfun(@(x) sscanf(x, '%f %f %f'), FC, 'UniformOutput', false);
% convert from cell array to numeric array
A = [A{:}].';

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More Answers (1)

Image Analyst
Image Analyst on 26 Nov 2013
Why not just use importdata() where you can tell it to throw away some number of headerlines?

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