Signal processing

Explanation of tables

*	green	Function exists in octave 2.0.x Noted incompatibilities and missing features
+	yellow	Function exists in matcompat Author and home for the function.
?	orange	Function doesn't exist Explanation of what you can do instead.
x	red	Function doesn't exist, and no work-around

Signals

x	diric
x	gauspuls
+	pulstran	Paul Kienzle
+	tripuls	Paul Kienzle
+	rectpuls	Paul Kienzle
x	sawtooth
*	sinc
x	square
+	chirp	Paul Kienzle
?	vco
?	modulate
?	demod	The Time-Frequency Tool box provides functions similar to vco, modulate and demod.
x	strips
+	specgram	Paul Kienzle
x	buffer

Filtering

+	fftfilt	extended by Paul Kienzle to handle matrices
+	filtfilt	Paul Kienzle; needs work
x	filtic
x	latcfilt
+	sgolayfilt	Paul Kienzle
x	sosfilt
+	medfilt1	Paul Kienzle; missing values and boundaries are ignored, not treated as zero.

Filter analysis

x	freqs
x	freqspace
+	freqz	Paul Kienzle adds many missing features
+	grpdelay	Paul Kienzle
+	impz	Paul Kienzle; but estimates decay poorly, and plots too long a response time.
+	zplane	Paul Kienzle; note that roots(poly(-ones(n,1))) does not equal -ones(n,1) for larger n (something about the roots of unity I expect), and your pole-zero positions will be significantly off.

Filter conversion

x	ac2poly
x	ac2rc
x	convmtx
x	latc2tf
x	poly2ac
x	poly2rc
x	rc2ac
x	rc2poly
?	residuez	Octave has residue; I don't know how it differs.
x	sos2ss
x	sos2tf
x	sos2zp
x	ss2sos
*	ss2tf
*	ss2zp
x	tf2latc
x	tf2sos
*	tf2ss
+	tf2zp	shadows control systems toolbox tf2zp; may want to delete it
x	zp2sos
*	zp2ss
+	zp2tf	shadows control systems toolbox zp2tf; may want to delete it
x	polystab

IIR Filter design

x	besself
+	butter	Paul Kienzle
+	cheby1	Paul Kienzle
+	cheby2	Paul Kienzle
x	ellip
x	maxflat
x	yulewalk
+	buttord	Paul Kienzle
+	cheb1ord	Paul Kienzle; provided by Laurent Mazet
x	cheb2ord
x	ellipord	butter, cheby1.m and cheby2 by Paul Kienzle have ap design code embedded in them
x	besselap
?	buttap
?	cheb1ap
?	cheb2ap
x	ellipap
?	lp2bp
?	lp2bs
?	lp2hp
?	lp2lp	Paul Kienzle has sftrans
+	bilinear	Paul Kienzle
x	impinvar

FIR filter design

+	fir1	Paul Kienzle
+	fir2	Paul Kienzle
x	fircls
x	fircls1
x	firls
x	firrcos
x	intfilt
x	kaiserord
x	cremez
+	remez	Adapted from Jake Janovetz; needs to be verified for correctness
x	remezord
+	sgolay	Paul Kienzle

Transforms

+	czt
+	dctmtx
+	dct2
+	idct2
+	dct
+	idct	Paul Kienzle
x	dftmtx
+	hilbert	Paul Kienzle; this is very similar to W. D. Kirby, April '98 version listed on octave-sources.
+	rceps	Paul Kienzle
+	cceps	Andreas Weingessel
x	icceps

Power spectrum analysis

+	pwelch	Paul Kienzle Paul Kienzle
+	tfe
+	cohere	Paul Kienzle; alternatively, wdkirby@ix.netcom.com posted a version to octave-sources.
+	csd	Paul Kienzle
+	pburg	Paul Kienzle
x	pcov
x	pmcov
x	pmtm
x	dpss
x	dpssclear
x	dpssdir
x	dpssload
x	dpsssave
?	pmusic	SPC Tools
+	pyulear	Paul Kienzle
+	xcorr	Paul Kienzle; fft-based so faster but less accurate
+	xcorr2	Paul Kienzle; not checked for correctness; fft-based so faster but less accurate; has additional bias control
+	xcov	Paul Kienzle; fft-based so faster but less accurate

Window functions
Paul Kienzle adds gaussian

*	bartlett
*	blackman
+	boxcar	Paul Kienzle
x	chebwin
*	hamming
*	hanning
+	kaiser	Kurt Hornik
+	triang	Paul Kienzle

System identification

+	arburg	Paul Kienzle
?	arcov	SPC Tools has ar_covar
?	armcov	SPC Tools has ar_mdcov
+	aryule	Paul Kienzle; like yulewalker, but takes a signal rather than an autocorrelation estimate and returns directly usable filter coefficients.
x	invfreqs
x	invfreqz
+	levinson	Paul Kienzle; like durbinlevinson but vectorized and returns directly usable filter coefficients.
x	lpc
?	prony	SPC Tools has ar_prony
x	rlevinson
x	stmcb

Sample rate change

+	decimate	Paul Kienzle
+	interp	Paul Kienzle
+	resample	Paul Kienzle ; needs work
x	upfirdn

GUI tools

x

sptool