Pulling Columns by Name in CSV Files

2024 6 24
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更新时间：2024 6 24
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Hello! I am having trouble with pulling specific data. I am trying to read a .csv file and grab specific columns by name, not by the column number/position. The data I a looking to grab doesnt't always end up in the same column.
CurrentData = readtable('data.csv','ReadVariableNames',1);
TimeData = CurrentData(:, 1); % Column A data ( time in seconds )
I have time data as a specific column since it is always in the first column. Here is some code I've tried from other threads but I now have an issue with the size -
[data, text] = readtable('5DV20WLRCJ010__671_edited.csv');
Throttle = strcmpi(text(1,:),'d ThrottleAct');
A = data(:,Throttle);
'd ThrottleAct' is the column I am trying to pull, but the data too large when I try this method - that and I don't fully understand it, haha. The data I am using is a 2567x468 table, and sometimes there are more or less variables.
Here is the error I get:
Error using readtable
Too many output arguments.
Error in project_testing (line 22)
[data, text] = readtable('data.csv');
I think it is having trouble with the read table, but I'm not sure of a better way to read the data and column headers as well as keeping it in this format.
Thanks for the help in advance

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Cris LaPierre
Cris LaPierre 2024-6-24
编辑：Cris LaPierre 2024-6-24

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See this page: Access Data in Tables
Also, consider using readtimetable instead of a readtable.
CurrentData = readtimetable('data.csv','ReadVariableNames',1);
TimeData = CurrentData(:, 1); % Column A data ( time in seconds )
Throttle = currentData.("d ThrottleAct")

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Samantha
Samantha 2024-6-24
Thank you! This worked, what would be the benfit to using readtimetable instead of a readtable? I briefly read the link to the name, but it seems very similar to readtable
Cris LaPierre
Cris LaPierre 2024-6-24
Timetables have some additional methods that can be helpful when working wiht time-series data. Basically, it recognizes that the data is tied to specific time points, and allows you to leverage that when combining or resampling your data.
If you don't need to do that, then just useing readtable is fine.
Samantha
Samantha 2024-6-24
I think I'll use the readtimetable function then, thank you for explaining it! It sounds like it'll come in handy

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