Append values in a new column

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Ioannis Doumanis
Ioannis Doumanis on 7 Dec 2021
Commented: Cris LaPierre on 20 Dec 2021
Hello all
The code below overwrites the previous values in the column Delay and inserts only the last ones (20). There should be a way to append the array instead of overwriting it but I dont know how. Any help will be appreciated
if contains(baseFileName,"A01")
x{k} = readtable(fullFileName,opts)
bigtable = vertcat(x{:})
bigtable(:,'Delay') = {10}
elseif contains(baseFileName,"A02")
x{k} = readtable(fullFileName,opts)
bigtable = vertcat(x{:})
bigtable(:,'Delay') = {20}
end

Answers (2)

Cris LaPierre
Cris LaPierre on 7 Dec 2021
If your tables have the same variable names (order does not matter), then just use square brackets.
newTable = readtable(fullFileName,opts)
bigtable = [bigtable;newTable];
  5 Comments
Ioannis Doumanis
Ioannis Doumanis on 8 Dec 2021
I am reading a specific data sample (300 samples) from several csv files. I want the samples the one after the other. I tried bigtable.Delay(1:6000) = 10; and still does not work. The table is filled with 0s instead of 10s and 20s. Currently I get correctly only the result (30) of the last condition of sth switch statement.
Cris LaPierre
Cris LaPierre on 20 Dec 2021
Consider sharing your data files. You can attach them using the paperclip icon.

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Ioannis Doumanis
Ioannis Doumanis on 8 Dec 2021
I also tried this. I still get 0s for the first two conditions. I am not sure why
delayvalues = [delayvalues; delay];
for k = 1 : length(theFiles)
baseFileName = theFiles(k).name;
fullFileName = fullfile(theFiles(k).folder, baseFileName);
% add column at the end of the table
switch true
case (contains(baseFileName,"A01"))
x{k} = readtable(fullFileName,opts)
bigtable = vertcat(x{:})
delay = 10;
bigtable(1:6000,'Delay') = delayvalues(1);
case (contains(baseFileName,"A02"))
x{k} = readtable(fullFileName,opts)
bigtable = vertcat(x{:})
delay = 20;
bigtable(6000:12000,'Delay') = delayvalues(2);
case (contains(baseFileName,"A03"))
x{k} = readtable(fullFileName,opts)
bigtable = vertcat(x{:})
delay = 30;
bigtable(12000:18000,'Delay') = delayvalues(3);
otherwise
% do nothing
end

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