How to read every nth line of a file
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time,n0v_soma,n1v_soma,n2v_soma,n3v_dend
0,-70,-70,-66.5,-66.5
0.027,-69.9703,-69.9794,-66.4966,-66.4966
0.054,-69.9685,-69.9533,-66.4933,-66.4933
0.081,-69.9283,-69.9322,-66.49,-66.4899
0.108,-69.9588,-69.9385,-66.4866,-66.4866
0.135,-69.9422,-69.8965,-66.4833,-66.4833
0.162,-69.9058,-69.8943,-66.48,-66.48
0.189,-69.8465,-69.8618,-66.4767,-66.4766
0.216,-69.8505,-69.8258,-66.4734,-66.4733
0.243,-69.7855,-69.8011,-66.4701,-66.47
0.27,-69.7913,-69.7594,-66.4668,-66.4667
0.297,-69.7228,-69.7291,-66.4636,-66.4634
0.324,-69.6841,-69.7006,-66.4603,-66.4601
0.351,-69.6907,-69.7157,-66.4571,-66.4569
0.378,-69.6584,-69.7295,-66.4538,-66.4536
0.405,-69.5766,-69.7279,-66.4506,-66.4503
0.432,-69.5668,-69.6756,-66.4474,-66.447
0.459,-69.5396,-69.6777,-66.4442,-66.4437
0.486,-69.511,-69.6717,-66.441,-66.4404
0.513,-69.4808,-69.6523,-66.4378,-66.4371
0.54,-69.4632,-69.6325,-66.4346,-66.4339
0.567,-69.4605,-69.6169,-66.4314,-66.4306
0.594,-69.4398,-69.6346,-66.4282,-66.4273
0.621,-69.4638,-69.6245,-66.4251,-66.424
0.648,-69.4429,-69.5968,-66.4219,-66.4207
0.675,-69.4134,-69.5639,-66.4187,-66.4174
0.702,-69.3973,-69.5655,-66.4156,-66.4141
0.729,-69.3973,-69.5668,-66.4125,-66.4108
0.756,-69.3611,-69.6189,-66.4093,-66.4075
My file looks something like this. I want to read every 10th line of this and skip the header.
so
my array should look like this
C=[0.216,-69.8505,-69.8258,-66.4734,-66.4733;0.486,-69.511,-69.6717,-66.441,-66.4404;0.756,-69.3611,-69.6189,-66.4093,-66.4075];
and so on
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Accepted Answer
Walter Roberson
on 13 Jul 2016
Sometimes it is just easier to loop reading and discarding most lines and storing the ones you want.
But if you need it done in one step:
per_line = 5;
every_nth_line = 10;
fmt = [repmat('*%f', 1, per_line*(every_nth_line-1)), repmat('%f', 1, per_line)];
fid = fopen('YourFile.txt', 'rt');
datacell = textscan(fid, fmt, 'delimiter', ',\n', 'HeaderLines', 1, 'CollectOutput', 1);
fclose(fid);
C = datacell{1};
3 Comments
Walter Roberson
on 13 Jul 2016
Sorry, minor typo. Change
fmt = [repmat('*%f', 1, per_line*(every_nth_line-1)), repmat('%f', 1, per_line)];
to
fmt = [repmat('%*f', 1, per_line*(every_nth_line-1)), repmat('%f', 1, per_line)];
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