nengolib.signal.discrete2cont(sys, dt, method='zoh', alpha=None)[source]

Convert linear system from discrete to continuous time-domain.

This is the inverse of cont2discrete(). This will not work in general, for instance with the ZOH method when the system has discrete poles at 0 (e.g., systems with pure time-delay elements).

sys : linear_system_like

Linear system representation.

dt : float

Time-step used to undiscretize sys.

method : string, optional

Method of discretization. Defaults to zero-order hold discretization ('zoh'), which assumes that the input signal is held constant over each discrete time-step.

alpha : float or None, optional

Weighting parameter for use with method='gbt'.

continuous_sys : LinearSystem

Continuous linear system (analog=True).


Converting a double-exponential synapse back and forth between domains:

>>> from nengolib.signal import discrete2cont, cont2discrete
>>> from nengolib import DoubleExp
>>> sys = DoubleExp(0.005, 0.2)
>>> assert dsys == discrete2cont(cont2discrete(sys, dt=0.1), dt=0.1)