Port regression test 452 to Pytests

testsuite/pytests/sli2py_regressions/test_ticket_452.py

@@ -0,0 +1,75 @@
+# -*- coding: utf-8 -*-
+#
+# test_ticket_452.py
+#
+# This file is part of NEST.
+#
+# Copyright (C) 2004 The NEST Initiative
+#
+# NEST is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 2 of the License, or
+# (at your option) any later version.
+#
+# NEST is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with NEST.  If not, see <http://www.gnu.org/licenses/>.
+import nest
+import numpy as np
+import pytest
+
+
+def run_simulation(model, simcommand):
+    """
+    Helper function to run simulations based on the model and simulation command.
+    Returns the spike times recorded by the spike recorder.
+    """
+    nest.ResetKernel()
+    nest.SetKernelStatus({"tics_per_ms": 8, "resolution": 0.125})  # 0.125 ms resolution
+
+    neuron = nest.Create(model, params={"I_e": 500.0})
+    pg = nest.Create("poisson_generator_ps", params={"rate": 10000.0, "start": 0.0})
+    sr = nest.Create("spike_recorder")
+
+    nest.Connect(pg, neuron, syn_spec={"delay": 1.0, "weight": 1.0})
+    nest.Connect(neuron, sr)
+
+    simcommand()
+
+    # Retrieve spike times from the spike recorder
+    events = nest.GetStatus(sr, "events")[0]
+    return events["times"]
+
+
+def test_ticket_452():
+    """
+    Ensure that simulations with precise spike timing yield identical results
+    independent of whether one simulates the full simulation time without interruption,
+    or splits the simulation into many small pieces.
+
+    Note: The problem was unrelated to the setting of kernel property  /off_grid_spiking
+    and the spike_recorder property  /precise_times.
+
+    Author: Hans Ekkehard Plesser, 2010-09-30; based on original reproduced code by Alexander Hanuschkin
+    """
+    models = ["iaf_psc_delta_ps", "iaf_psc_alpha_ps"]
+
+    # Define two different simulation approaches
+    def simulate_continuous():
+        nest.Simulate(500.0)
+
+    def simulate_stepped():
+        for _ in range(500):  # Simulate 500 steps of 1.0 ms each
+            nest.Simulate(1.0)
+
+    # Test each model with both simulation approaches
+    for model in models:
+        spike_times_continuous = run_simulation(model, simulate_continuous)
+        spike_times_stepped = run_simulation(model, simulate_stepped)
+
+        # Check if the spike times are identical for both simulation approaches
+        np.testing.assert_array_equal(spike_times_continuous, spike_times_stepped)