How to read a large CSV in chunks;

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

0 voti

If you want to read specific range of the generated csv file you can use one of the following :
  • csvread
  • dlmread
  • xlsread

Categorie

Scopri di più su Data Import and Analysis in Centro assistenza e File Exchange

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Release

R2017b

Richiesto:

il 23 Ago 2018

Risposto:

il 28 Ago 2018

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