Help files and functions

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+function [psd,f_out] = pburg(x,poles,freq,Fs,range,method,plot_type,criterion)
+//Calculate Burg maximum-entropy power spectral density.
+//Calling Sequence
+//[psd,f_out] = pburg(x,poles,freq,Fs,range,method,plot_type,criterion)
+//All but the first two arguments are optional and may be empty.
+//Parameters 
+//   x:       [vector] sampled data
+//   poles:    [integer scalar] required number of poles of the AR model
+//   freq:     [real vector] frequencies at which power spectral density is calculated [integer scalar] number of uniformly distributed frequency values at which spectral density is calculated.    [default=256]
+//   Fs:       [real scalar] sampling frequency (Hertz) [default=1]
+//   range:    'half',  'onesided' : frequency range of the spectrum is from zero up to but not including sample_f/2.  Power from negative frequencies is added to the positive side of the spectrum.   'whole', 'twosided' : frequency range of the spectrum is -sample_f/2 to sample_f/2, with negative frequencies stored in "wrap around" order after the positive frequencies; e.g. frequencies for a 10-point 'twosided' spectrum are 0 0.1 0.2 0.3 0.4 0.5 -0.4 -0.3 -0.2 -0.1 'shift', 'centerdc' : same as 'whole' but with the first half of the spectrum swapped with second half to put the zero-frequency value in the middle. (See "help fftshift". If "freq" is vector, 'shift' is ignored. If model coefficients "ar_coeffs" are real, the default range is 'half', otherwise default range is 'whole'.
+//   method:   'fft':  use FFT to calculate power spectral density. 'poly': calculate spectral density as a polynomial of 1/z N.B. this argument is ignored if the "freq" argument is a vector.  The default is 'poly' unless the "freq" argument is an integer power of 2.
+// plot_type:  'plot', 'semilogx', 'semilogy', 'loglog', 'squared' or 'db' specifies the type of plot.  The default is 'plot', which means linear-linear axes. 'squared' is the same as 'plot'. 'dB' plots "10*log10(psd)".  This argument is ignored and a spectrum is not plotted if the caller requires a returned value.
+// criterion:  [optional string arg]  model-selection criterion.  Limits the number of poles so that spurious poles are not added when the whitened data has no more information in it (see Kay & Marple, 1981). Recognized values are 'AKICc' -- approximate corrected Kullback information  criterion (recommended), 'KIC'  -- Kullback information criterion  'AICc' -- corrected Akaike information criterion 'AIC'  -- Akaike information criterion 'FPE'  -- final prediction error" criterion The default is to NOT use a model-selection criterion.
+//Description
+//This function is being called from Octave
+//This function is a wrapper for arburg and ar_psd.
+//The functions "arburg" and "ar_psd" do all the work.
+//See "help arburg" and "help ar_psd" for further details.
+//Examples
+//a = [1.0 -1.6216505 1.1102795 -0.4621741 0.2075552 -0.018756746];
+//[psd,f_out] = pburg(a,2);
+
+funcprot(0);
+lhs = argn(1)
+rhs = argn(2)
+if (rhs < 2 | rhs > 8)
+error("Wrong number of input arguments.")
+end
+
+select(rhs)
+	
+	case 2 then
+		if(lhs==1)
+		psd = callOctave("pburg",x,poless)
+		elseif(lhs==2)
+		[psd,f_out] = callOctave("pburg",x,poles)
+		else
+		error("Wrong number of output argments.")
+		end
+
+	case 3 then
+		if(lhs==1)
+		psd = callOctave("pburg",x,poles,freq)
+		elseif(lhs==2)
+		[psd,f_out] = callOctave("pburg",x,poles,freq)
+		else
+		error("Wrong number of output argments.")
+	       	end
+	case 4 then
+		if(lhs==1)
+		psd = callOctave("pburg",x,poles,freq,Fs)
+		elseif(lhs==2)
+		[psd,f_out] = callOctave("pburg",x,poles,freq,Fs)
+		else
+		error("Wrong number of output argments.")
+	       	end
+	case 5 then
+		if(lhs==1)
+		psd = callOctave("pburg",x,poles,freq,Fs,range)
+		elseif(lhs==2)
+		[psd,f_out] = callOctave("pburg",x,poles,freq,Fs,range)
+		else
+		error("Wrong number of output argments.")
+	       	end
+	case 6 then
+		if(lhs==1)
+		psd = callOctave("pburg",x,poles,freq,Fs,range,method)
+		elseif(lhs==2)
+		[psd,f_out] = callOctave("pburg",x,poles,freq,Fs,range,method)
+		else
+		error("Wrong number of output argments.")
+	       	end
+	case 7 then
+		if(lhs==1)
+		psd = callOctave("pburg",x,poles,freq,Fs,range,method,plot_type)
+		elseif(lhs==2)
+		[psd,f_out] = callOctave("pburg",x,poles,freq,Fs,range,method,plot_type)
+		else
+		error("Wrong number of output argments.")
+	       	end
+	case 8 then
+		if(lhs==1)
+		psd = callOctave("pburg",x,poles,freq,Fs,range,method,plot_type,criterion)
+		elseif(lhs==2)
+		[psd,f_out] = callOctave("pburg",x,poles,freq,Fs,range,method,plot_type,criterion)
+		else
+		error("Wrong number of output argments.")
+	       	end
+	end
+endfunction
+
+