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function varargout = pburg(varargin) %PBURG Power Spectrum estimate via Burg's method. % Pxx = PBURG(X,ORDER,NFFT) is the Power Spectral Density estimate, % Pxx(w), of signal vector X using Burg's method. ORDER is the model % order of the AR model equations. NFFT is the FFT length which % determines the frequency grid. Pxx is length (NFFT/2+1) for NFFT even, % (NFFT+1)/2 for NFFT odd, and NFFT if X is complex. % NFFT is optional; it defaults to 256. % % [Pxx,W] = PBURG(X,ORDER,NFFT) returns a vector of frequencies, W, % in rads/sample, at which the PSD is estimated. % % PBURG with no output arguments plots the PSD in the next available % figure. By default, PBURG will plot the magnitude over the % frequency interval [0,Pi] for a real signal vector X and over the % frequency interval [0,2*Pi] for a complex vector X. To plot the PSD % over the interval [0,2*Pi] for a real X use: % PBURG(X,ORDER,NFFT,'whole'). % % [Pxx,F] = PBURG(X,ORDER,NFFT,Fs) or PBURG(X,ORDER,NFFT,Fs,'whole') % return the PSD estimate and the vector of frequencies, F, in Hz, at % which the PSD is estimated. If left empty, Fs defaults to 1 Hz. If % no output arguments are given and Fs is specified, the plot will be % over the frequency interval [0,Fs/2] for a real signal vector X and % over the frequency interval [0,Fs] for a complex vector X. % % PBURG(X,ORDER,NFFT,Fs,'whole','squared') will plot the PSD estimate % directly instead of converting to decibels. % % You can obtain a default parameter for NFFT and Fs by inserting an % empty matrix [], e.g., PBURG(X,4,[],1000). % % See also PCOV, PYULEAR, PMTM, PMUSIC, PMCOV, PWELCH, PEIG, ARBURG % and PRONY. % Author(s): R. Losada % Copyright (c) 1988-98 by The MathWorks, Inc. % $Revision: 1.16.1.2 $ $Date: 1999/01/22 03:42:31 $ error(nargchk(2,6,nargin)) method = 'arburg'; titlestring = 'Burg PSD Estimate'; if nargout==0, pfreqz(method,titlestring,varargin{:}) else [varargout{1:nargout}] = pfreqz(method,titlestring,varargin{:}); end % [EOF] pburg.m