How to read a large CSV in chunks;

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ariane
ariane el 23 de Ag. de 2018
Respondida: Rishi Binda el 28 de Ag. de 2018
I have the following code which filters a very large CSV.
opts = detectImportOptions('Z_EnergySequence.dat');
data = readtable('Z_EnergySequence.dat',opts);
tol = 1e-6;
filter = 4.125;
filterreddata = data(abs(data.X - filter) < tol, :);
filteredions = data(ismember(data.IonN, filterreddata.IonN),:);
filteredions(1:2:end,:)= [];
writetable(filteredions, 'Published/Z_EnergySequence1.csv');
I think I may be getting errors in the data processing. Is there a way in which I can read the whole CSV in chunks and output to the same file?
  1 comentario
Jan
Jan el 23 de Ag. de 2018
Editada: Jan el 23 de Ag. de 2018
I think I may be getting errors in the data processing
This seems to be a pure speculation. Do not try to fix not existing problems.

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Respuestas (1)

Rishi Binda
Rishi Binda el 28 de Ag. de 2018
If you want to read specific range of the generated csv file you can use one of the following :
  • csvread
  • dlmread
  • xlsread

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