Ornstein-Uhlenbeck process ======================== Ornstein-Uhlenbeck process Figure 2: Two realizations of the Ornstein-Uhlenbeck process for parameters τ=1.0 and σ=0.1 (black curve), and for τ=0.1 and σ=0.31622 (red curve). In both cases the noise intensity is σ^2*τ=0.01 . The red curve represents a noise that more closely mimics Gaussian white noise. Both realizations begin here at x(0)=1.0 , after which the mean decays exponentially to zero with time constant τ. Andre Longtin (2010) Stochastic dynamical systems. Scholarpedia, 5(4):1619. Sebastian Schmitt, 2022 .. code-block:: python // ornstein_uhlenbeck.py from brian2 import * N = NeuronGroup( 1, """ tau : second sigma : 1 dy/dt = -y/tau + sqrt(2*sigma**2/tau)*xi : 1 """, method="euler" ) N.tau = 0.5 * second N.sigma = 0.1 N.y = 1 M = StateMonitor(N, "y", record=True) run(10 * second) .. code-block:: html
\[ \frac{dy}{dt} = -\frac{y}{\tau} + \sigma \xi(t) \]
0.5 s