Fs = 44100; % Sampling Frequency in Hz
y = wavread('armstrong'); % Reads the armstrong.wav file specificed by a string file
wavplay(y,Fs); % Plays the armstrong.wav file at the specified sampling frequency
x = wavread('armstrongforward'); % Reads the armstrongforward.wav file specificed by a string file
wavplay(x,Fs); % Plays the armstrongforward.wav file at the specified sampling frequency
N = length(x); % Returns the length of vector x.
k = 1:1:N; % Creates an array
minus_k = N+1 - k; % Reverses the created array
z = x(minus_k);
wavplay(z,Fs); % Plays the reversal of armstrongforward.wav file
w = zeros(1,2.*N);
w(1:2:2.*N) = z(1:N);
wavplay(w,Fs); % Plays the slowed & reversed version of armstrongforward.wav file