add ignore-and-fire neuron test

models/neurons/ignore_and_fire.nestml

@@ -0,0 +1,53 @@
+"""
+ignore_and_fire - Neuron generating spikes at fixed intervals irrespective of inputs
+######################################################################################  
+
+Description
++++++++++++
+
+The ``ignore_and_fire`` neuron is a neuron model generating spikes at a predefined ``firing_rate`` with a constant inter-spike interval ("fire"), irrespective of its inputs ("ignore"). In this simplest version of the ``ignore_and_fire`` neuron, the inputs from other neurons or devices are not processed at all (*). The ``ignore_and_fire`` neuron is primarily used for neuronal-network model verification and validation purposes, in particular, to evaluate the correctness and performance of connectivity generation and inter-neuron communication. It permits an easy scaling of the network size and/or connectivity without affecting the output spike statistics. The amount of network traffic is predefined by the user, and therefore fully controllable and predictable, irrespective of the network size and structure. 
+
+To create asynchronous activity for a population of ``ignore_and_fire`` neurons, the firing ``phase``s can be randomly initialised. Note that the firing ``phase`` is a real number, defined as the time to the next spike relative to the firing period.
+
+(*) The model can easily be extended and equipped with any arbitrary input processing (such as calculating input currents with alpha-function shaped PSC kernels or updating the gating variables in the Hodgkin-Huxley model) or (after-) spike generation dynamics to make it more similar and comparable to other non-ignorant neuron models. In such extended ignore_and_fire models, the spike emission process would still be decoupled from the intrinsic neuron dynamics.
+
+Authors
++++++++
+
+Tetzlaff (February 2021; January 2022)
+
+"""
+
+neuron ignore_and_fire:
+
+  state:
+    phase real = 1.                ## relative time to next spike (in (0,1])
+
+  parameters:
+    firing_rate Bq = 10. Bq        ## firing rate
+
+  internals:    
+    firing_period_steps integer = steps( 1. / firing_rate )    ## firing period in steps
+    phase_steps integer = steps( max(0.,phase) / firing_rate ) ## firing phase in steps
+
+  input:
+    spikes Bq <- spike   ## the neuron receives spikes, but is not processing them
+
+  output:
+    spike
+
+  update:
+   integrate_odes()
+   if phase_steps == 0:
+       emit_spike()
+       phase_steps = firing_period_steps - 1
+       #println("spike")
+    else:
+       phase_steps -= 1
+
+    phase = 1. * phase_steps / firing_period_steps
+
+    #println(" ")
+    #println("firing_period_steps={firing_period_steps}")
+    #println("phase_steps={phase_steps}")
+    #println("phase={phase}")

pynestml/codegeneration/nest_code_generator.py

@@ -281,7 +281,7 @@ def analyse_neuron(self, neuron: ASTNeuron) -> Tuple[Dict[str, ASTAssignment], D
             self.non_equations_state_variables[neuron.get_name()].extend(
                 ASTUtils.all_variables_defined_in_block(neuron.get_state_blocks()))
 
-            return [], [], [], []
+            return {}, {}, [], []
 
         if len(neuron.get_equations_blocks()) > 1:
             raise Exception("Only one equations block per model supported for now")

pynestml/transformers/synapse_post_neuron_transformer.py

@@ -223,6 +223,9 @@ def transform_neuron_synapse_pair_(self, neuron, synapse):
         new_neuron = neuron.clone()
         new_synapse = synapse.clone()
 
+        new_neuron.accept(ASTSymbolTableVisitor())
+        new_synapse.accept(ASTSymbolTableVisitor())
+
         assert len(new_neuron.get_equations_blocks()) <= 1, "Only one equations block per neuron supported for now."
         assert len(new_synapse.get_equations_blocks()) <= 1, "Only one equations block per synapse supported for now."
         assert len(new_neuron.get_state_blocks()) <= 1, "Only one state block supported per neuron for now."

tests/nest_tests/test_ignore_and_fire.py

@@ -0,0 +1,77 @@
+# -*- coding: utf-8 -*-
+#
+# test_ignore_and_fire.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 numpy as np
+import os
+import pytest
+
+import nest
+
+from pynestml.frontend.pynestml_frontend import generate_nest_target
+
+try:
+    import matplotlib
+    matplotlib.use("Agg")
+    import matplotlib.ticker
+    import matplotlib.pyplot as plt
+    TEST_PLOTS = True
+except Exception:
+    TEST_PLOTS = False
+
+
+class TestIgnoreAndFire:
+
+    neuron_model_name = "ignore_and_fire_nestml__with_stdp_nestml"
+    synapse_model_name = "stdp_nestml__with_ignore_and_fire_nestml"
+
+    @pytest.fixture(scope="module", autouse=True)
+    def setUp(self):
+        """Generate the model code"""
+
+        codegen_opts = {"neuron_synapse_pairs": [{"neuron": "ignore_and_fire",
+                                                  "synapse": "stdp",
+                                                  "post_ports": ["post_spikes"]}]}
+
+        files = [os.path.join("models", "neurons", "ignore_and_fire.nestml"),
+                 os.path.join("models", "synapses", "stdp_synapse.nestml")]
+        input_path = [os.path.realpath(os.path.join(os.path.dirname(__file__), os.path.join(
+            os.pardir, os.pardir, s))) for s in files]
+        generate_nest_target(input_path=input_path,
+                             logging_level="DEBUG",
+                             suffix="_nestml",
+                             codegen_opts=codegen_opts)
+
+    def test_ignore_and_fire_with_stdp(self):
+        pre_spike_times = [10., 40., 50.]
+        resolution = 1.    # [ms]
+        sim_time = 100.   # [ms]
+
+        nest.set_verbosity("M_ALL")
+        nest.Install("nestmlmodule")
+        nest.ResetKernel()
+        nest.SetKernelStatus({"resolution": resolution})
+
+        pre_neuron = nest.Create(self.neuron_model_name)
+        post_neuron = nest.Create(self.neuron_model_name)
+
+        nest.Connect(pre_neuron, post_neuron, syn_spec={"synapse_model": self.synapse_model_name})
+
+        nest.Simulate(sim_time)