How to delete every nth lines in a .txt file?

Hi!

How to delete every nth line in a text file using MATLAB?

Let's say I have a text file, in which I want to delete 4 lines, every 5 lines, starting at n=1:

data0

data1

data2

data3

data4

data5

data6

data7

data8

data9

data10

data11

... up to 500

The data in bold is the one I want to keep in the text file, and in Italic is the data I want to erase from my text file in Matlab.

So at the end I obtain a file with 100 values, and I deleted 400 values. Can I do that with Matlab? Thank you for your help.

Answer 1

[Adam Danz]

You'll need to read the text file into matlab, then delete every nth row using something like

data(1:n:end,:) = [];

Then you'll need to write the data back to a text file or overwrite the one you read from.

Answer 2

[Walter Roberson]

filename = 'YourFile.txt';
newfilename = 'YourNewFile.txt';   %recommended to be a different file than the input file
S = regexp( fileread(filename), '\r?\n', 'split');

T = S(5:5:end);

fid = fopen(newfilename, 'wt');
fprintf(fid, '%s\n', T{:});
fclose(fid)