Main Content

Analysis Methods for Filter System Objects

MethodDescription
Single-rate and Multirate Analysis
fvtoolFilter visualization tool
infoFilter information
freqzFrequency response of a discrete-time filter
phasezPhase response of a discrete-time filter
zerophaseZero-phase response of a discrete-time filter
grpdelayGroup delay of a discrete-time filter
phasedelayPhase delay of a discrete-time filter
impzImpulse response of a discrete-time filter
impzlengthImpulse response length
stepzStep response of a discrete-time filter
zplanePole/Zero plot
costCost estimate
measureMeasure filter response
orderFilter order
firtypeDetermine the type (1–4) of a linear phase FIR filter
coeffsReturn filter coefficients
Multirate Analysis
polyphasePolyphase decomposition of multirate filters
gainGain of a Cascaded Integrator-Comb (CIC) filter
Second-order Sections
scaleScale second-order sections
scalecheckCheck scale of second-order sections
scaleoptsCreate options object for sos scaling
cumsecVector of cumulative second-order section filters
reorderReorder second-order sections
sosConvert IIR filter to Biquad filter
Code Generation
realizemdlFilter realization diagram
Fixed-point (supported by FIRFilter, IIRFilter, AllpoleFilter, and BiquadFilter only)
noisepsdPower spectral density of filter output due to roundoff noise
noisepsdoptsCreate options object for noisepsd computation
freqrespestFrequency response estimate via filtering
freqrespoptsCreate options object for frequency response estimate
Other
isallpassTrue for allpass discrete-time filter
islinphaseTrue for linear discrete-time filter
ismaxphaseTrue if maximum phase
isminphaseTrue if minimum phase
isrealTrue for discrete-time filter with real coefficients
isstableTrue if the filter is stable
isfirTrue if the filter is FIR
issosTrue if filter is in second order sections form
specifyallSpecify all fixed-point properties