Help files and functions

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+function res = qp_kaiser (nb, at, linear)
+//Computes a finite impulse response (FIR) filter for use with a quasi-perfect reconstruction polyphase-network filter bank.
+//Calling Sequence
+//qp_kaiser (nb, at, linear)
+//qp_kaiser (nb, at)
+//Parameters 
+//nb: Number of bands
+//at: Attenuation
+//linear: When not zero, minimum-phase calculation is omitted.
+//Description
+//This is an Octave function.
+//This version utilizes a Kaiser window to shape the frequency response of the designed filter. Tha number nb of bands and the desired attenuation at in the stop-band are given as parameters.
+//
+//The Kaiser window is multiplied by the ideal impulse response h(n)=a.sinc(a.n) and converted to its minimum-phase version by means of a Hilbert transform.
+//Examples
+// qp_kaiser (5, 5, 1)
+//ans =
+//
+//   0.11591   0.25606   0.25606   0.25606   0.11591
+
+funcprot(0);
+lhs = argn(1)
+rhs = argn(2)
+if (rhs < 2 | rhs > 3)
+error("Wrong number of input arguments.")
+end
+
+select(rhs)
+	
+	case 2 then
+	res = callOctave("qp_kaiser", nb, at)
+
+	case 3 then
+	res = callOctave("qp_kaiser", nb, at, linear)
+
+	end
+endfunction