How to read a large CSV in chunks;

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ariane
ariane il 23 Ago 2018
Risposto: Rishi Binda il 28 Ago 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 Commento
Jan
Jan il 23 Ago 2018
Modificato: Jan il 23 Ago 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.

Accedi per commentare.

Risposte (1)

Rishi Binda
Rishi Binda il 28 Ago 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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