You load the data into the struct data_line, but yu do not save the loaded structure. Instead, you cat(1) something that starts out as the numeric value 1, together with something that is a character vector that is the file name.
Try
full_val = 1;
path_directory='C:\Users\me\Desktop\test_data';
original_files=dir([path_directory '/*.mat']);
nfiles = length(original_files);
full_val = cell(nfiles, 2);
for k=1:length(original_files)
filename=[path_directory '/' original_files(k).name];
original_files(k).name = strtok(original_files(k).name, '.mat');
disp(original_files(k).name)
data_line = load(filename);
full_val(k, :) = {filename, data_line};
end
Though what I suspect you would want would be
fn = fieldnames(data_line);
full_val(k, :) = {filename, data_line.(fn{1})};
This extracts the first variable's value out of the loaded file.
