Signal Processing Toolbox

Function Category List

The tables below list all of the Signal Processing Toolbox functions by category.

Filter Analysis
abs	Absolute value (magnitude).
angle	Phase angle.
freqs	Frequency response of analog filters.
freqspace	Frequency spacing for frequency response.
freqz	Compute the frequency response of digital filters.
freqzplot	Plot frequency response data.
grpdelay	Compute the average filter delay (group delay).
impz	Compute the impulse response of digital filters.
unwrap	Unwrap phase angles.
zplane	Zero-pole plot.

Filter Implementation
conv	Convolution and polynomial multiplication.
conv2	Two-dimensional convolution.
deconv	Deconvolution and polynomial division.
fftfilt	FFT-based FIR filtering using the overlap-add method.
filter	Filter data with a recursive (IIR) or nonrecursive (FIR) filter.
filter2	Two-dimensional digital filtering.
filtfilt	Zero-phase digital filtering.
filtic	Find initial conditions for a transposed direct form II filter implementation.
latcfilt	Lattice and lattice-ladder filter implementation.
medfilt1	One-dimensional median filtering.
sgolayfilt	Savitzky-Golay filtering.
sosfilt	Second-order (biquadratic) IIR digital filtering.
upfirdn	Upsample, apply an FIR filter, and downsample.

FIR Digital Filter Design
convmtx	Convolution matrix.
cremez	Complex and nonlinear-phase equiripple FIR filter design.
fir1	Design a window-based finite impulse response filter.
fir2	Design a frequency sampling-based finite impulse response filter.
fircls	Constrained least square FIR filter design for multiband filters.
fircls1	Constrained least square filter design for lowpass and highpass linear phase FIR filters.
firls	Least square linear-phase FIR filter design.
firrcos	Raised cosine FIR filter design.
intfilt	Interpolation FIR filter design.
kaiserord	Estimate parameters for an FIR filter design with Kaiser window.
remez	Compute the Parks-McClellan optimal FIR filter design.
remezord	Parks-McClellan optimal FIR filter order estimation.
sgolay	Savitzky-Golay filter design.

IIR Digital Filter Design--Classical and Direct
butter	Butterworth analog and digital filter design.
cheby1	Chebyshev type I filter design (passband ripple).
cheby2	Chebyshev type II filter design (stopband ripple).
ellip	Elliptic (Cauer) filter design.
maxflat	Generalized digital Butterworth filter design.
prony	Prony's method for time-domain IIR filter design.
stmcb	Compute a linear model using Steiglitz-McBride iteration.
yulewalk	Recursive digital filter design.

IIR Filter Order Estimation
buttord	Calculate the order and cutoff frequency for a Butterworth filter.
cheb1ord	Calculate the order for a Chebyshev type I filter.
cheb2ord	Calculate the order for a Chebyshev type II filter.
ellipord	Calculate the minimum order for elliptic filters.

Analog Lowpass Filter Prototypes
besselap	Bessel analog lowpass filter prototype.
buttap	Butterworth analog lowpass filter prototype.
cheb1ap	Chebyshev type I analog lowpass filter prototype.
cheb2ap	Chebyshev type II analog lowpass filter prototype.
ellipap	Elliptic analog lowpass filter prototype.

Analog Filter Design
besself	Bessel analog filter design.
butter	Butterworth analog and digital filter design.
cheby1	Chebyshev type I filter design (passband ripple).
cheby2	Chebyshev type II filter design (stopband ripple).
ellip	Elliptic (Cauer) filter design.

Analog Filter Transformation
lp2bp	Transform lowpass analog filters to bandpass.
lp2bs	Transform lowpass analog filters to bandstop.
lp2hp	Transform lowpass analog filters to highpass.
lp2lp	Change the cut-off frequency for a lowpass analog filter.

Filter Discretization
bilinear	Bilinear transformation method for analog-to-digital filter conversion.
impinvar	Impulse invariance method for analog-to-digital filter conversion.

Linear System Transformations
latc2tf	Convert lattice filter parameters to transfer function form.
polystab	Stabilize a polynomial.
polyscale	Scale the roots of a polynomial.
residuez	z-transform partial-fraction expansion.
sos2ss	Convert digital filter second-order section parameters to state-space form.
sos2tf	Convert digital filter second-order section data to transfer function form.
sos2zp	Convert digital filter second-order sections parameters to zero-pole-gain form.
ss2sos	Convert digital filter state-space parameters to second-order sections form.
ss2tf	Convert state-space filter parameters to transfer function form.
ss2zp	Convert state-space filter parameters to zero-pole-gain form.
tf2latc	Convert transfer function filter parameters to lattice filter form.
tf2sos	Convert digital filter transfer function data to second-order sections form.
tf2ss	Convert transfer function filter parameters to state-space form.
tf2zp	Convert transfer function filter parameters to zero-pole-gain form.
zp2sos	Convert digital filter zero-pole-gain parameters to second-order sections form.
zp2ss	Convert zero-pole-gain filter parameters to state-space form.
zp2tf	Convert zero-pole-gain filter parameters to transfer function form.

Windows
bartlett	Compute a Bartlett window.
blackman	Compute a Blackman window.
boxcar	Compute a rectangular window.
chebwin	Compute a Chebyshev window.
hamming	Compute a Hamming window.
hann	Compute the Hann (Hanning) window.
kaiser	Compute a Kaiser window.
triang	Compute a triangular window.

Transforms
czt	Chirp z-transform.
dct	Discrete cosine transform (DCT).
dftmtx	Discrete Fourier transform matrix.
fft	Compute the one-dimensional fast Fourier transform.
fft2	Compute the two-dimensional fast Fourier transform.
fftshift	Rearrange the outputs of the FFT functions.
hilbert	Compute the discrete-time analytic signal using the Hilbert transform.
idct	Inverse discrete cosine transform.
ifft	One-dimensional inverse fast Fourier transform.
ifft2	Two-dimensional inverse fast Fourier transform.

Cepstral Analysis
cceps	Complex cepstral analysis.
icceps	Inverse complex cepstrum.
rceps	Real cepstrum and minimum phase reconstruction.

Statistical Signal Processing and Spectral Analysis
cohere	Estimate magnitude squared coherence function between two signals.
corrcoef	Compute the correlation coefficient matrix.
corrmtx	Compute a data matrix for autocorrelation matrix estimation.
cov	Compute the covariance matrix.
csd	Estimate the cross spectral density (CSD) of two signals.
pburg	Estimate the power spectral density using the Burg method.
pcov	Estimate the power spectral density using the covariance method.
peig	Estimate the pseudospectrum using the eigenvector method.
periodogram	Estimate the power spectral density (PSD) of a signal using a periodogram.
pmcov	Estimate the power spectral density using the modified covariance method.
pmtm	Estimate the power spectral density using the multitaper method (MTM).
pmusic	Estimate the power spectral density using MUSIC algorithm.
psdplot	Plot power spectral density (PSD) data.
pwelch	Estimate the power spectral density (PSD) of a signal using Welch's method.
pyulear	Estimate the power spectral density using the Yule-Walker AR method.
rooteig	Estimate frequency and power content using the eigenvector method.
rootmusic	Estimate frequency and power content using the root MUSIC algorithm.
tfe	Estimate the transfer function from input and output.
xcorr	Estimate the cross-correlation function.
xcorr2	Estimate the two-dimensional cross-correlation.
xcov	Estimate the cross-covariance function (equal to mean-removed cross-correlation).

Parametric Modeling
arburg	Compute an estimate of AR model parameters using the Burg method.
arcov	Compute an estimate of AR model parameters using the covariance method.
armcov	Compute an estimate of AR model parameters using the modified covariance method.
aryule	Compute an estimate of AR model parameters using the Yule-Walker method.
ident	See the System Identification Toolbox documentation.
invfreqs	Identify continuous-time filter parameters from frequency response data.
invfreqz	Identify discrete-time filter parameters from frequency response data.
prony	Prony's method for time domain IIR filter design.
stmcb	Compute a linear model using Steiglitz-McBride iteration.

Linear Prediction
ac2poly	Convert an autocorrelation sequence to prediction polynomial.
ac2rc	Convert an autocorrelation sequence to reflection coefficients.
is2rc	Convert inverse sine parameters to reflection coefficients.
lar2rc	Convert log area ratio parameters to reflection coefficients.
levinson	Compute the Levinson-Durbin recursion.
lpc	Compute linear prediction filter coefficients.
lsf2poly	Convert line spectral frequencies to a prediction filter coefficients.
poly2ac	Convert a prediction filter polynomial to an autocorrelation sequence.
poly2lsf	Convert prediction filter coefficients to line spectral frequencies.
poly2rc	Convert a prediction filter polynomial to reflection coefficients.
rc2ac	Convert reflection coefficients to an autocorrelation sequence.
rc2is	Convert reflection coefficients to inverse sine parameters.
rc2lar	Convert reflection coefficients to log area ratio parameters.
rc2poly	Convert reflection coefficients to a prediction filter polynomial.
rlevinson	Compute the reverse Levinson-Durbin recursion.
schurrc	Compute reflection coefficients from an autocorrelation sequence.

Multirate Signal Processing
decimate	Decrease the sampling rate for a sequence (decimation).
interp	Increase sampling rate by an integer factor (interpolation).
interp1	One-dimensional data interpolation (table lookup).
resample	Change sampling rate by any rational factor.
spline	Cubic spline interpolation.
upfirdn	Upsample, apply an FIR filter, and downsample.

Waveform Generation
chirp	Generate a swept-frequency cosine.
diric	Compute the Dirichlet or periodic sinc function.
gauspuls	Generate a Gaussian-modulated sinusoidal pulse.
gmonopuls	Generate a Gaussian monopulse.
pulstran	Generate a pulse train.
rectpuls	Generate a sampled aperiodic rectangle.
sawtooth	Generate a sawtooth or triangle wave.
sinc	Sinc function.
square	Generate a square wave.
tripuls	Generate a sampled aperiodic triangle.
vco	Voltage controlled oscillator.

Specialized Operations
buffer	Buffer a signal vector into a matrix of data frames.
cell2sos	Convert a cell array for second-order sections to a second-order section matrix.
cplxpair	Group complex numbers into complex conjugate pairs.
demod	Demodulation for communications simulation.
dpss	Discrete prolate spheroidal sequences (Slepian sequences).
dpssclear	Remove discrete prolate spheroidal sequences from database.
dpssdir	Discrete prolate spheroidal sequences database directory.
dpssload	Load discrete prolate spheroidal sequences from database.
dpsssave	Save discrete prolate spheroidal sequences in database.
eqtflength	Make the lengths of a transfer function's numerator and denominator equal.
modulate	Modulation for communications simulation.
seqperiod	Compute the period of a sequence.
sos2cell	Convert a second-order section matrix to cell arrays.
specgram	Time-dependent frequency analysis (spectrogram).
stem	Plot discrete sequence data.
strips	Strip plot.
udecode	Decode 2n-level quantized integer inputs to floating-point outputs.
uencode	Quantize and encode floating-point inputs to integer outputs.

Graphical User Interfaces
fdatool	Open the Filter Design and Analysis Tool.
sptool	Interactive digital signal processing tool (SPTool).

Function Reference

Alphabetical List of Functions