Merge pull request #515 from apdavison/issue511

Raise an Exception if the spike times given to SpikeSourceArray are not ordered

pyNN/brian/cells.py

@@ -10,6 +10,7 @@
 import numpy
 import brian
 from pyNN.parameters import Sequence, simplify
+from pyNN import errors
 from . import simulator
 
 mV = brian.mV
@@ -252,6 +253,7 @@ def __init__(self, n, equations, spike_times=None):
         Note that `equations` is not used: it is simply for compatibility with
         other NeuronGroup subclasses.
         """
+        self._check_spike_times(spike_times)
         spiketimes = [(i, t) for i, seq in enumerate(spike_times) for t in seq.value]
         brian.SpikeGeneratorGroup.__init__(self, n, spiketimes,
                                            clock=simulator.state.network.clock)
@@ -267,9 +269,16 @@ def _set_spike_times(self, spike_times, mask=None):
             existing_times = self._get_spike_times()
             existing_times[mask] = spike_times
             spike_times = existing_times
+        self._check_spike_times(spike_times)
         values = [(i, t) for i, seq in enumerate(spike_times) for t in seq.value]
         brian.SpikeGeneratorGroup.__init__(self, self.N, values, period=self.period)
     spike_times = property(fget=_get_spike_times, fset=_set_spike_times)
 
+    def _check_spike_times(self, spike_times):
+        for seq in spike_times:
+            if numpy.any(seq.value[:-1] > seq.value[1:]):
+                raise errors.InvalidParameterValueError(
+                    "Spike times given to SpikeSourceArray must be in increasing order")
+
     def initialize(self):
         pass

pyNN/nest/populations.py

@@ -141,6 +141,8 @@ def _create_cells(self):
         except nest.NESTError as err:
             if "UnknownModelName" in err.args[0] and "cond" in err.args[0]:
                 raise errors.InvalidModelError("%s Have you compiled NEST with the GSL (Gnu Scientific Library)?" % err)
+            if "Spike times must be sorted in non-descending order" in err.args[0]:
+                raise errors.InvalidParameterValueError("Spike times given to SpikeSourceArray must be in increasing order")
             raise  # errors.InvalidModelError(err)
         # create parrot neurons if necessary
         if hasattr(self.celltype, "uses_parrot") and self.celltype.uses_parrot:

pyNN/neuron/cells.py

@@ -9,6 +9,7 @@
 
 import logging
 from math import pi
+import numpy
 from neuron import h, nrn, hclass
 
 from pyNN import errors
@@ -572,6 +573,8 @@ def _set_spike_times(self, spike_times):
             self._spike_times = h.Vector(spike_times.value)
         except (RuntimeError, AttributeError):
             raise errors.InvalidParameterValueError("spike_times must be an array of floats")
+        if numpy.any(spike_times.value[:-1] > spike_times.value[1:]):
+            raise errors.InvalidParameterValueError("Spike times given to SpikeSourceArray must be in increasing order")
         self.play(self._spike_times)
 
     def _get_spike_times(self):

test/system/scenarios/test_cell_types.py

@@ -8,7 +8,8 @@
 except ImportError:
     have_scipy = False
 import quantities as pq
-from nose.tools import assert_greater, assert_less
+from nose.tools import assert_greater, assert_less, assert_raises
+from pyNN.errors import InvalidParameterValueError
 
 from .registry import register
 
@@ -261,6 +262,16 @@ def test_SpikeSourcePoissonRefractory(sim, plot_figure=False):
 test_SpikeSourcePoissonRefractory.__test__ = False
 
 
+
+@register()
+def issue511(sim):
+    """Giving SpikeSourceArray an array of non-ordered spike times should produce an InvalidParameterValueError error"""
+    sim.setup()
+    celltype = sim.SpikeSourceArray(spike_times=[[2.4, 4.8, 6.6, 9.4], [3.5, 6.8, 9.6, 8.3]])
+    assert_raises(InvalidParameterValueError, sim.Population, 2, celltype)
+
+
+
 # todo: add test of Izhikevich model
 
 
@@ -275,3 +286,4 @@ def test_SpikeSourcePoissonRefractory(sim, plot_figure=False):
     test_SpikeSourcePoisson(sim, plot_figure=args.plot_figure)
     test_SpikeSourceGamma(sim, plot_figure=args.plot_figure)
     test_SpikeSourcePoissonRefractory(sim, plot_figure=args.plot_figure)
+    issue511(sim)