How to make a list of iddata objects

I'm loading data from a bunch of csv files and making each one into a iddata object.

How do I create a collection from the resulting iddata objects?

I thought cell arrays were the way to go (as described here) but I'm getting a criptic error

Code snippet:

% Store data sets in this cell array
dataSets = {};
 
% Loop through files
for k = 1 : length(theFiles)
    file = theFiles{1, k};
    fprintf(1, "Reading file '%s'\n", file.name);
    filePath = fullfile(file.folder, file.name);
    % Read data from file
    dataTable = readtable(filePath);
    % Create dataset object for system identification
    inputData = table2array(dataTable(:,2:3));
    outputData = table2array(dataTable(:,4:5));
    dataSet = iddata(outputData,inputData);
    dataSets = [dataSets, dataSet]; 
end

The line

dataSets = [dataSets, dataSet];

generates this error message:

Undefined function 'realdata' for input arguments of type 'cell'.

Error in iddata/horzcat (line 19)
reald = realdata(dat);

[Bill Tubbs]

I've tried googling this error message and there are no search results on the internet.

Answer 1

[Bill Tubbs]

Here is a solution. Use the index to assign to the cell array:

% Loop through files
for k = 1 : length(theFiles)
    file = theFiles{1, k};
    fprintf(1, "Reading file '%s'\n", file.name);
    filePath = fullfile(file.folder, file.name);
    % Read data from file
    dataTable = readtable(filePath);
    % Create dataset object for system identification
    inputData = table2array(dataTable(:,2:3));
    outputData = table2array(dataTable(:,4:5));
    dataSet = iddata(outputData,inputData);
    dataSets{k} = dataSet; 
end