Scilab Function

Signal - Signal manual description

### FILTERS

- analpf : analog low-pass filter
- buttmag : squared magnitude response of a Butterworth filter
- casc : creates cascade realization of filter
- cheb1mag : square magnitude response of a type 1 Chebyshev filter
- cheb2mag : square magnitude response of a type 1 Chebyshev filter
- chepol : recursive implementation of Chebychev polynomial
- convol : convolution of 2 discrete series
- ell1 mag : squared magnitude of an elliptic filter
- eqfir : minimax multi-band, linear phase, FIR filter
- eqiir : design of iir filter
- faurre : optimal lqg filter.
- lindquis : optimal lqg filter lindquist algorithm
- ffilt : FIR low-pass,high-pass, band-pass, or stop-band filter
- filter : compute the filter model
- find_freq : parameter compatibility for elliptic filter design
- findm : for elliptic filter design
- frmag : magnitude of the frequency responses of FIR and IIR filters.
- fsfirlin : design of FIR, linear phase (frequency sampling technique)
- fwiir : optimum design of IIR filters in cascade realization,
- iir : designs an iir digital filter using analog filter designs.
- iirgroup : group delay of iir filter
- iirlp : Lp IIR filters optimization
- group : calculate the group delay of a digital filter
- optfir : optimal design of linear phase filters using linear programming
- remezb : minimax approximation of a frequency domain magnitude response.
- kalm : Kalman update and error variance
- lev : resolve the Yule-Walker equations :
- levin : solve recursively Toeplitz system (normal equations)
- srfaur : square-root algorithm for the algebraic Riccati equation.
- srkf : square-root Kalman filter algorithm
- sskf : steady-state Kalman filter
- system : generates the next observation given the old state
- trans : transformation of standardized low-pass filter into low-pass, high-pass, band-pass, stop-band.
- wfir : linear-phase windowed FIR low-pass, band-pass, high-pass, stop-band
- wiener : Wiener estimate (forward-backward Kalman filter formulation)
- wigner : time-frequency wigner spectrum of a signal.
- window : calculate symmetric window
- zpbutt : Butterworth analog filter
- zpch1 : poles of a type 1 Chebyshev analog filter
- zpch2 : poles and zeros of a type 2 Chebyshev analog filter
- zpell : poles and zeros of prototype lowpass elliptic filter

### Spectral estimation

- corr : correlation coefficients
- cspect : spectral estimation using the modified periodogram method.
- czt : chirp z-transform algorithm
- intdec : change the sampling rate of a 1D or 2D signal
- mese : calculate the maximum entropy spectral estimate
- pspect : auto and cross-spectral estimate
- wigner : Wigner-Ville time/frequency spectral estimation

### Transforms

- dft : discrete Fourier transform
- fft : fast flourier transform
- hilb : Hilbert transform centred around the origin.
- hank : hankel matrix of the covariance sequence of a vector process
- mfft : fft for a multi-dimensional signal

### identification

- lattn,lattp : recursive solution of normal equations
- phc : State space realisation by the principal hankel component approximation method,
- rpem : identification by the recursive prediction error method

### MISCELLANEOUS

- lgfft : computes p = ceil (log_2(x))
- sinc : calculate the function sin(2*pi*fl*t)/(pi*t)
- sincd : calculates the function Sin(N*x)/Sin(x)
- %k : Jacobi's complete elliptic integral
- %asn : .TP the elliptic integral :
- %sn : Jacobi 's elliptic function with parameter m
- bilt : bilinear transform or biquadratic transform.
- jmat : permutes block rows or block columns of a matrix