Importing large .csv files into MATLAb but confined by limits of excel

So I am using an Arduino to collect many values over a long period of time. I am storing these values in a CSV file. Excel does not let you exceed 1048576 rows in one file. However, that is only 8 minutes worth of data for me and I want to collect about 24 hours of data. Now I thought, I will just open the file straight in matlab, surely matlab doesnt have a restriction such as this one. To my dismay, when I open up my file in MATLAB it only shows me 1048576 rows, just like excel. So does matlab have a restriction? When I open the disk the .csv file is written on, there is a small excel icon next to it (by default I am supposing). Does this mean when I import it into Matlab, it is importing it not only as a .csv file but also as an excel file, and the restrictions of excel are imposed upon it? I am using uigetfile to open it up. Thank you

[Stephen23]

uigetfile does not load any data files, so it is unclear how you are loading this data into MATLAB.

Answer 1

[Titus Edelhofer]

Hi Patrick,

the importer you mention will use xlsread in the background and yes, would be limited by the same limit.

But: nobody stops you from reading the file directly, the easiest will be to use a datastore:

doc datastore

Hope this helps,

Titus

[Patrick Lydon]

Thank you for the reply. So just to clarify the reasoning behind this: xlsread uses the excel application to open the file, therefore it is under the confines of excel, while doc datastore goes around excel and gets the file directly from the disk with no application as a vessel?

[Titus Edelhofer]

Exactly. xlsread uses Excel as ActiveX Server application. It's convenient to use to import csv files, therefore using Excels engine. But it's not needed, datastore (or even textscan as a somewhat lower level function) reads csv files as text files, not through Excel.

[Walter Roberson]

If you use the 'basic' option of xlsread then it will not use excel. Also readtable will not use excel

[Katrina Anderson]

Hi,

I am having the same issue. However, I am uploading data from an IMU device and I think it is uploaded on to the computer as a .csv

Is there anyway I can get around that?

Thanks

Katrina