Extract data with a loop cycle from structure

Hi,

I need to extract data from structure iteratively as multiple tables.

The response with this code is: 'Unable to use a value of type cell as an index.'

Furthemore I'd like to plot the extracted data.

Many thanks,

Code:

directory = '/Users/Dati/';
S = dir(fullfile(directory,'*.csv')); 
for k = 1:numel(S)
    F = fullfile(directory,S(k).name);
    S(k).data = readtable(F, 'PreserveVariableNames', true, 'ReadVariableNames', true);
end


for i = 1: numel(S)
out(i) = S({i}).data;
end 

Answer 1

[Ameer Hamza]

The correct syntax is

directory = '/Users/Dati/';
S = dir(fullfile(directory,'*.csv')); 
for k = 1:numel(S)
    F = fullfile(directory,S(k).name);
    S(k).data = readtable(F, 'PreserveVariableNames', true, 'ReadVariableNames', true);
end

out = cell(1, numel(S))
for i = 1: numel(S)
out{i} = S(i).data;
end

You need to store the tables in a cell array.

Also, second for-loop is not needed. Following is equivalent

directory = '/Users/Dati/';
S = dir(fullfile(directory,'*.csv')); 
for k = 1:numel(S)
    F = fullfile(directory,S(k).name);
    S(k).data = readtable(F, 'PreserveVariableNames', true, 'ReadVariableNames', true);
end

out = {S.data};

[Stefano Alberti]

Thank you very much Ameer.

Do you have any suggestion about how to 'extract' data from structure, put into a table (as double) and do some operation with that.

Many thanks

[Ameer Hamza]

Your data is already in table format. Can you explain more? Also, it is better if you run the first for-loop and attach the data in the struct 'S' in a .mat file.

[Stefano Alberti]

Thanks again Ameer!

I'd like to extract data from the structure, with a dedicated table for each table inside structure.

After that for each column of each table I'd like to apply movmean.

Maybe it is not a good approach 'extract' data but directly apply the movmean to each column inside the structure.

Hope to be clear,

Thanks again.

[Ameer Hamza]

The data in the tables are not in numeric format. It is the form of character arrays. Also, there are several columns with text data. How do you decide which column do you want to apply movmean().