spectrum analysis code in MaTLaB(urgently required)

% Audio spectrum display. To exit, close the figure.
%
Fs = 22050;                                 % sample rate, hertz
T  = 0.2;                                   % sample duration, seconds
Hs = spectrum.welch('blackman',1024,20);    % configure the transform
gca;                                        % open the figure
while get(0,'CurrentFigure')                % while figure still open
  signal = wavrecord(T*Fs,Fs);              % acquire some signal
  psd(Hs, signal,'Fs',Fs); ylim([-160 0]);  % transform and plot
  pause(0.001);                             % allow figure to update
end

% Audio spectrum display. To exit, close the figure.
%
fs = 22050;                                 % sample rate, hertz
N = 1024;                                   % duration, samples
window = blackman(N);                       % weighting
window = window / mean(window);             % normalize it
gca;                                        % open the figure
while get(0,'CurrentFigure')                % while figure still open
  y = wavrecord(N, fs);                     % acquire some signal
  h = fft(y .* window);                     % transform
  plot(fs*(0:N/2)/N, 20*log10(max(2/N*abs(h(1:N/2+1)), 1e-10)));
  ylim([-160 20]); xlabel('Hertz'); ylabel('dB');
  drawnow;                                  % allow figure to update
end

% Audio spectrum display. To exit, close the figure.
%
fs = 22050;                                 % sample rate, hertz
N = 1024;                                   % duration, samples
window = blackman(N);                       % weighting
window = window / mean(window);             % normalize it
gca;                                        % open the figure
while get(0,'CurrentFigure')                % while figure still open
  y = wavrecord(N, fs);                     % acquire some signal
  h = fft(y .* window);                     % transform
  plot(fs*(0:N/2)/N, 20*log10(max(2/N*abs(h(1:N/2+1)), 1e-10)));
  ylim([-160 20]); xlabel('Hertz'); ylabel('dB');
  drawnow;                                  % allow figure to update
end

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MATLAB Version 7.0.4.365 (R14) Service Pack 2


Java VM Version: Java 1.5.0 with Sun Microsystems Inc. Java HotSpot(TM) Client VM
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MATLAB                                                Version 7.0.4      (R14SP2)
Simulink                                              Version 6.2        (R14SP2)
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Control System Toolbox                                Version 6.2        (R14SP2)
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Simulink Control Design                               Version 1.2        (R14SP2)
Simulink Fixed Point                                  Version 5.1        (R14SP2)
Stateflow                                             Version 6.2        (R14SP2)

% Audio spectrum display
fs = 22050;                                 % sample rate, hertz
N = 1024;                                   % duration, samples
y = wavrecord(N, fs);                       % acquire some signal
h = fft(y);                                 % transform
plot(fs*(0:N/2)/N, 20*log10(max(2/N*abs(h(1:N/2+1)), 1e-10)));
ylim([-160 20]); xlabel('Hertz'); ylabel('dB');