control.matlab.series

control.matlab.series(sys1, sys2[, ..., sysn])[source]

Series connection of I/O systems.

Generates a new system [sysn * ... *] sys2 * sys1.

Parameters:

sys1, sys2, …, sysnscalar, array, or InputOutputSystem: I/O systems to combine.

Returns:

outInputOutputSystem: Series interconnection of the systems.

Other Parameters:

inputs, outputsstr, or list of str, optional: List of strings that name the individual signals. If not given, signal names will be of the form ‘s[i]’ (where ‘s’ is one of ‘u, or ‘y’). See InputOutputSystem for more information.
statesstr, or list of str, optional: List of names for system states. If not given, state names will be of the form ‘x[i]’ for interconnections of linear systems or ‘<subsys_name>.<state_name>’ for interconnected nonlinear systems.
namestring, optional: System name (used for specifying signals). If unspecified, a generic name ‘sys[id]’ is generated with a unique integer id.

Raises:

ValueError: If sys2.ninputs does not equal sys1.noutputs or if sys1.dt is not compatible with sys2.dt.

See also

append, feedback, interconnect, negate, parallel

Notes

This function is a wrapper for the __mul__ function in the appropriate NonlinearIOSystem, StateSpace, TransferFunction, or other I/O system class. The output type is the type of sys1 unless a more general type is required based on type type of sys2.

If both systems have a defined timebase (dt = 0 for continuous time, dt > 0 for discrete time), then the timebase for both systems must match. If only one of the system has a timebase, the return timebase will be set to match it.

Examples

>>> G1 = ct.rss(3)
>>> G2 = ct.rss(4)
>>> G = ct.series(G1, G2) # Same as sys3 = sys2 * sys1
>>> G.ninputs, G.noutputs, G.nstates
(1, 1, 7)

>>> G1 = ct.rss(2, inputs=2, outputs=3)
>>> G2 = ct.rss(3, inputs=3, outputs=1)
>>> G = ct.series(G1, G2) # Same as sys3 = sys2 * sys1
>>> G.ninputs, G.noutputs, G.nstates
(2, 1, 5)