% data file
filename='es01.txt';

% open the file
f = fopen(filename, 'rt');
% read the data
g = fscanf(f, '%f');

% alternatively, the following instruction could be used
%g = load(filename);

% compute the mean
m = mean(g);
fprintf('mean: %f\n', m);

% sorting
x = sort(g);

% graph
plot(x, exp(-x.^2));

