def test_GetTargetNodes(self):
"""Interface check for finding targets."""
cdict = {
'rule': 'pairwise_bernoulli',
'p': 1.,
'mask': {
'grid': {
'shape': [2, 2]
}
}
}
sdict = {'synapse_model': 'stdp_synapse'}
nest.ResetKernel()
nest.SetKernelStatus({
'sort_connections_by_source': False,
'use_compressed_spikes': False
})
layer = nest.Create('iaf_psc_alpha',
positions=nest.spatial.grid(shape=[3, 3],
extent=(2., 2.),
edge_wrap=True))
# connect layer -> layer
nest.Connect(layer, layer, cdict, sdict)
t = nest.GetTargetNodes(layer[0], layer)
self.assertEqual(len(t), 1)
t = nest.GetTargetNodes(layer, layer)
self.assertEqual(len(t), len(layer))
# 2x2 mask -> four targets
self.assertTrue(all([len(g) == 4 for g in t]))
t = nest.GetTargetNodes(layer, layer, syn_model='static_synapse')
self.assertEqual(len(t), len(layer))
self.assertTrue(all([len(g) == 0 for g in t])) # no static syns
t = nest.GetTargetNodes(layer, layer, syn_model='stdp_synapse')
self.assertEqual(len(t), len(layer))
self.assertTrue(all([len(g) == 4
for g in t])) # 2x2 mask -> four targets
t = nest.GetTargetNodes(layer[0], layer)
self.assertEqual(len(t), 1)
self.assertEqual(t[0], nest.NodeCollection([1, 2, 4, 5]))
t = nest.GetTargetNodes(layer[4], layer)
self.assertEqual(len(t), 1)
self.assertEqual(t[0], nest.NodeCollection([5, 6, 8, 9]))
t = nest.GetTargetNodes(layer[8], layer)
self.assertEqual(len(t), 1)
self.assertEqual(t[0], nest.NodeCollection([1, 3, 7, 9]))
# extract position information, transpose to list of x, y and z positions
xpos, ypos, zpos = zip(*nest.GetPosition(l1))
fig = plt.figure()
ax = fig.add_subplot(111, projection='3d')
ax.scatter(xpos, ypos, zpos, s=15, facecolor='b')
# Gaussian connections in full box volume [-0.75,0.75]**3
nest.Connect(l1, l1,
{'rule': 'pairwise_bernoulli',
'p': nest.spatial_distributions.gaussian(nest.spatial.distance, std=0.25),
'allow_autapses': False,
'mask': {'box': {'lower_left': [-0.75, -0.75, -0.75],
'upper_right': [0.75, 0.75, 0.75]}}})
# show connections from center element
# sender shown in red, targets in green
ctr = nest.FindCenterElement(l1)
xtgt, ytgt, ztgt = zip(*nest.GetTargetPositions(ctr, l1)[0])
xctr, yctr, zctr = nest.GetPosition(ctr)
ax.scatter([xctr], [yctr], [zctr], s=40, facecolor='r')
ax.scatter(xtgt, ytgt, ztgt, s=40, facecolor='g', edgecolor='g')
tgts = nest.GetTargetNodes(ctr, l1)[0]
distances = nest.Distance(ctr, l1)
tgt_distances = [d for i, d in enumerate(distances) if i + 1 in tgts]
plt.figure()
plt.hist(tgt_distances, 25)
plt.show()