How to import data from different sessions of an experiment within the same script?

Hey there,

I'm currently conducting a study regarding memory capability. The study is designed as a within-subject experiment. Participants have to complete two sessions (on two seperate days). The data is located in two seperate folders for each participant. Now I try to find a way to import the data from both sessions into one script to perform analysis separately (for each session) and then combine these results.

The way is was doing it so far is the following (importing data from session 1, the same for session 2):

subfiles = dir('../Desktop/results/sourcedata/participant-3*/ses-1/behav/*task-memory.mat')

subjects = {}

if isempty(subjects)
    % select all in subdir
    subjects = NaN(1,length(subfiles));
    for i = 1:length(subfiles)
        subjects(i) = str2double(subfiles(i).name(end-22:end-20));
    end
end

results = struct();

for subjn = 1:length(subjects)
if subjn <= length(subjects)
        %% get the subjects data
        temp_data_bundle = load(fullfile(subfiles(subjn).folder, subfiles(subjn).name))
end
end

for subjn = 1:length(subjects)
    if subjn <= length(subjects)
     temp_data_bundle = load(fullfile(subfiles(subjn).folder, subfiles(subjn).name))

    else
        temp_data = results(end).subdata.data;
    end

     results(subjn).name = temp_data_bundle.parameters.subject_nr;

I'm using an existing script which is shared in my workgroup and adding my specific analysis to it. I know that there are various ways to import data but which one might be suitable for me?

I appreciate any advice. Thanks!

Answer 1

[Vatsal]

Hi,

The script is using the 'dir' function to find all the .mat files in a directory for each session. After that, it is using 'load' to open each file. To manage data from more sessions, the script can be updated to loop through the sessions.

sessions = 1:2; % number of sessions
subjects = {}; % initialize subjects
results = struct(); % initialize results

for s = sessions
    subfiles = dir(['../Desktop/results/sourcedata/participant-3*/ses-' num2str(s) '/behav/*task-memory.mat']);
    if isempty(subjects)
        subjects = NaN(1,length(subfiles));
        for i = 1:length(subfiles)
            subjects(i) = str2double(subfiles(i).name(end-22:end-20));
        end
    end
    for subjn = 1:length(subjects)
        if subjn <= length(subjects)
            temp_data_bundle = load(fullfile(subfiles(subjn).folder, subfiles(subjn).name));
            results(subjn).name = temp_data_bundle.parameters.subject_nr;
            results(subjn).session(s).data = temp_data_bundle; % store data for each session
        end
    end
end

I hope this helps!