control.bode(syslist, omega=None, dB=None, Hz=None, deg=None, Plot=True, *args, **kwargs)

Bode plot for a system

Plots a Bode plot for the system over a (optional) frequency range.


syslist : linsys

List of linear input/output systems (single system is OK)

omega : freq_range

Range of frequencies (list or bounds) in rad/sec

dB : boolean

If True, plot result in dB

Hz : boolean

If True, plot frequency in Hz (omega must be provided in rad/sec)

deg : boolean

If True, return phase in degrees (else radians)

Plot : boolean

If True, plot magnitude and phase

*args, **kwargs:

Additional options to matplotlib (color, linestyle, etc)


mag : array (list if len(syslist) > 1)


phase : array (list if len(syslist) > 1)


omega : array (list if len(syslist) > 1)



1. Alternatively, you may use the lower-level method (mag, phase, freq) = sys.freqresp(freq) to generate the frequency response for a system, but it returns a MIMO response.

2. If a discrete time model is given, the frequency response is plotted along the upper branch of the unit circle, using the mapping z = exp(j omega dt) where omega ranges from 0 to pi/dt and dt is the discrete time base. If not timebase is specified (dt = True), dt is set to 1.


>>> sys = ss("1. -2; 3. -4", "5.; 7", "6. 8", "9.")
>>> mag, phase, omega = bode(sys)