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Rational Fitting and Time Domain Analysis

Fit frequency domain data to rational function, calculate time, step, impulse, and frequency response

Use the rationalfit function to fit data defined in the frequency domain with an equivalent Laplace transfer function. Using rational function fitting you can create simple models for a required accuracy, model order reduction, zero phase on extrapolation to DC, and causal modeling system among other advantages.


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rationalPerform rational fitting to complex frequency-dependent data
rfmodel.rationalPerform rational fit using pole-residue representation of the component
rationalfitApproximate data using stable rational function object
timerespTime response for rational objects
steprespStep-signal response for rational object and rationalfit function object
freqrespFrequency response of rational object and rationalfit function object
pwlresp Calculate time response of piecewise linear input signal
impulseImpulse response for rational function object
ispassiveReturn true if rationalfit output is passive at all frequencies
makepassiveEnforce passivity of rationalfit output or a rational object
passivityPlot passivity of N-by-N rationalfit function output
iscausalDetermine if data is causal at specified frequency
abcdConstruct state-space matrices from rational object
zpkCompute zeros, poles, and gain of rational object
writevaGenerate Verilog-A description of rational object
generateSPICEGenerate SPICE file from rationalfit of S-parameters