How to store several tables in one table using a loop

I want to store several csv files into tables which I then store in one table in order to plot them easily. Storing one csv file into one table works perfectly. Matlab won't use my counter for the for-loop as table fieldname, so it overwrites the first entry. This is my code so far:

counter = 1;
filename = ['measurement' sprintf( '%03d', counter) '.csv'];
while exist(filename, 'file') == 2
    filename = ['measurement' sprintf( '%03d', counter) '.csv']
    T.counter = readtable(filename) % this isn't working
    counter = counter + 1;
end

The output is a 1x1 table T with the csv content named 'counter'. What I'd like to have is a n x 1 table T with n equals the amount of csv files.

Answer 1

[Ameer Hamza]

Creating a table of tables might not be a good strategy. The usual way is to create a cell array of tables. The following code shows an example

files = dir('measurement*.csv');
T = cell(size(files));
for i = 1:numel(files)
    T{i} = readtable(files(i).name) % this isn't working
end

[Tamara Szecsey]

This works perfectly, when I am in the directory where all the measurement*.csv are. But it doesn't work, if I what do execute it from one directory above like this

files=dir('directory_above/measurement*.csv')

The matlab executable file is one directory higher than 'directory_above' and I can execute it, if I add the path (matlab is asking, when I descent into 'directory_above') but now I want to execute this code for several directories.

The error message is:

Error using readtable (line 245)
Unable to find or open 'measurement001.csv'. Check the path and filename or file permissions.

Error in Vergleich_ohne_p_mit_p_20map (line 18)
    T{i} = readtable(files(i).name);

[Ameer Hamza]

You can create the full path to the file

files = dir('measurement*.csv');
T = cell(size(files));
for i = 1:numel(files)
    pathname = fullfile(files(i).folder, files(i).name)
    T{i} = readtable(pathname) % this isn't working
end

[Tamara Szecsey]

Thank you, for the fast answer.

I'd like to open several files from different directories. So for example, i am in home, where the .m file is, and there are directory1 and directory2. In those directories, there are several measurement*.csv files.

I could use cd, but I don't know how to use cd recursive, so matlab would add the measurements of every directory to the T table.

[Ameer Hamza]

Write it like this

files = dir('*/measurement*.csv');

[Tamara Szecsey]

Even though the pathname is correct, the same error message occurs.

But it seems that I figured out how to plot several files of different directories by creating a new script for every directory and running the script in between hold on and hold off:

clc;
clear;
close all;

figure;
grid on;
hold on;

run('script1.m')
for i = 1:size(T)
    Tnew{i,1}=T{i,1}
end
run('script2.m')
for i = 1:size(T)
    Tnew{i,2}=T{i,1}
end
[r,c] = size(Tnew)
for j = 1:r
    plot(t,Tnew{j,1}.(3), '-k')
end
hold off;

And script1.m and script2.m looks like your first answer just with a cd command in the beginning and cd ../ for exiting the directory again.