changed edge correction for single spikes

Spike trains with single spikes now only get auxiliary spikes at the edges
for the SPIKE distance instead of real spikes before.

1 files changed, 35 insertions, 32 deletions

diff --git a/pyspike/cython/cython_profiles.pyx b/pyspike/cython/cython_profiles.pyx
index f08de6e..4a42cdb 100644
--- a/pyspike/cython/cython_profiles.pyx
+++ b/pyspike/cython/cython_profiles.pyx
@@ -63,18 +63,18 @@ def isi_profile_cython(double[:] s1, double[:] s2,
     # first interspike interval - check if a spike exists at the start time
     if s1[0] > t_start:
         # edge correction
-        nu1 = fmax(s1[0]-t_start, s1[1]-s1[0])
+        nu1 = fmax(s1[0]-t_start, s1[1]-s1[0]) if N1 > 1 else s1[0]-t_start
         index1 = -1
     else:
-        nu1 = s1[1]-s1[0]
+        nu1 = s1[1]-s1[0] if N1 > 1 else t_end-s1[0]
         index1 = 0
 
     if s2[0] > t_start:
         # edge correction
-        nu2 = fmax(s2[0]-t_start, s2[1]-s2[0])
+        nu2 = fmax(s2[0]-t_start, s2[1]-s2[0]) if N2 > 1 else s2[0]-t_start
         index2 = -1
     else:
-        nu2 = s2[1]-s2[0]
+        nu2 = s2[1]-s2[0] if N2 > 1 else t_end-s2[0]
         index2 = 0
 
     isi_values[0] = fabs(nu1-nu2)/fmax(nu1, nu2)
@@ -92,7 +92,8 @@ def isi_profile_cython(double[:] s1, double[:] s2,
                     nu1 = s1[index1+1]-s1[index1]
                 else:
                     # edge correction
-                    nu1 = fmax(t_end-s1[index1], nu1)
+                    nu1 = fmax(t_end-s1[index1], nu1) if N1 > 1 \
+                          else t_end-s1[index1]
             elif (index2 < N2-1) and ((index1 == N1-1) or
                                       (s1[index1+1] > s2[index2+1])):
                 index2 += 1
@@ -101,7 +102,8 @@ def isi_profile_cython(double[:] s1, double[:] s2,
                     nu2 = s2[index2+1]-s2[index2]
                 else:
                     # edge correction
-                    nu2 = fmax(t_end-s2[index2], nu2)
+                    nu2 = fmax(t_end-s2[index2], nu2) if N2 > 1 \
+                          else t_end-s2[index2]
             else: # s1[index1+1] == s2[index2+1]
                 index1 += 1
                 index2 += 1
@@ -110,12 +112,14 @@ def isi_profile_cython(double[:] s1, double[:] s2,
                     nu1 = s1[index1+1]-s1[index1]
                 else:
                     # edge correction
-                    nu1 = fmax(t_end-s1[index1], nu1)
+                    nu1 = fmax(t_end-s1[index1], nu1) if N1 > 1 \
+                          else t_end-s1[index1]
                 if index2 < N2-1:
                     nu2 = s2[index2+1]-s2[index2]
                 else:
                     # edge correction
-                    nu2 = fmax(t_end-s2[index2], nu2)
+                    nu2 = fmax(t_end-s2[index2], nu2) if N2 > 1 \
+                          else t_end-s2[index2]
             # compute the corresponding isi-distance
             isi_values[index] = fabs(nu1 - nu2) / fmax(nu1, nu2)
             index += 1
@@ -191,9 +195,9 @@ def spike_profile_cython(double[:] t1, double[:] t2,
     N1 = len(t1)
     N2 = len(t2)
 
-    # we can assume at least two spikes per spike train
-    assert N1 > 1
-    assert N2 > 1
+    # we can assume at least one spikes per spike train
+    assert N1 > 0
+    assert N2 > 0
 
     spike_events = np.empty(N1+N2+2)
 
@@ -205,26 +209,26 @@ def spike_profile_cython(double[:] t1, double[:] t2,
         # t_p1 = t_start
         # t_p2 = t_start
         # auxiliary spikes for edge correction - consistent with first/last ISI 
-        t_aux1[0] = fmin(t_start, t1[0]-(t1[1]-t1[0]))
-        t_aux1[1] = fmax(t_end, t1[N1-1]+(t1[N1-1]-t1[N1-2]))
-        t_aux2[0] = fmin(t_start, t2[0]-(t2[1]-t2[0]))
-        t_aux2[1] = fmax(t_end, t2[N2-1]+(t2[N2-1]-t2[N2-2]))
+        t_aux1[0] = fmin(t_start, 2*t1[0]-t1[1]) if N1 > 1 else t_start
+        t_aux1[1] = fmax(t_end, 2*t1[N1-1]-t1[N1-2]) if N1 > 1 else t_end
+        t_aux2[0] = fmin(t_start, 2*t2[0]-t2[1]) if N2 > 1 else t_start
+        t_aux2[1] = fmax(t_end, 2*t2[N2-1]-t2[N2-2]) if N2 > 1 else t_end
         t_p1 = t_start if (t1[0] == t_start) else t_aux1[0]
         t_p2 = t_start if (t2[0] == t_start) else t_aux2[0]
         if t1[0] > t_start:
             # dt_p1 = t2[0]-t_start
             t_f1 = t1[0]
             dt_f1 = get_min_dist_cython(t_f1, t2, N2, 0, t_aux2[0], t_aux2[1])
-            isi1 = fmax(t_f1-t_start, t1[1]-t1[0])
+            isi1 = fmax(t_f1-t_start, t1[1]-t1[0]) if N1 > 1 else t_f1-t_start
             dt_p1 = dt_f1
             # s1 = dt_p1*(t_f1-t_start)/isi1
             s1 = dt_p1
             index1 = -1
         else:
-            t_f1 = t1[1]
+            t_f1 = t1[1] if N1 > 1 else t_end
             dt_f1 = get_min_dist_cython(t_f1, t2, N2, 0, t_aux2[0], t_aux2[1])
-            dt_p1 = 0.0
-            isi1 = t1[1]-t1[0]
+            dt_p1 = get_min_dist_cython(t_p1, t2, N2, 0, t_aux2[0], t_aux2[1])
+            isi1 = t_f1-t1[0]
             s1 = dt_p1
             index1 = 0
         if t2[0] > t_start:
@@ -232,15 +236,15 @@ def spike_profile_cython(double[:] t1, double[:] t2,
             t_f2 = t2[0]
             dt_f2 = get_min_dist_cython(t_f2, t1, N1, 0, t_aux1[0], t_aux1[1])
             dt_p2 = dt_f2
-            isi2 = fmax(t_f2-t_start, t2[1]-t2[0])
+            isi2 = fmax(t_f2-t_start, t2[1]-t2[0]) if N2 > 1 else t_f2-t_start
             # s2 = dt_p2*(t_f2-t_start)/isi2
             s2 = dt_p2
             index2 = -1
         else:
-            t_f2 = t2[1]
+            t_f2 = t2[1] if N2 > 1 else t_end
             dt_f2 = get_min_dist_cython(t_f2, t1, N1, 0, t_aux1[0], t_aux1[1])
-            dt_p2 = 0.0
-            isi2 = t2[1]-t2[0]
+            dt_p2 = get_min_dist_cython(t_p2, t1, N1, 0, t_aux1[0], t_aux1[1])
+            isi2 = t_f2-t2[0]
             s2 = dt_p2
             index2 = 0
 
@@ -273,7 +277,8 @@ def spike_profile_cython(double[:] t1, double[:] t2,
                     s1 = dt_p1
                 else:
                     dt_f1 = dt_p1
-                    isi1 = fmax(t_end-t1[N1-1], t1[N1-1]-t1[N1-2])
+                    isi1 = fmax(t_end-t1[N1-1], t1[N1-1]-t1[N1-2]) if N1 > 1 \
+                           else t_end-t1[N1-1]
                     # s1 needs adjustment due to change of isi1
                     # s1 = dt_p1*(t_end-t1[N1-1])/isi1
                     # Eero's correction: no adjustment
@@ -305,7 +310,8 @@ def spike_profile_cython(double[:] t1, double[:] t2,
                     s2 = dt_p2
                 else:
                     dt_f2 = dt_p2
-                    isi2 = fmax(t_end-t2[N2-1], t2[N2-1]-t2[N2-2])
+                    isi2 = fmax(t_end-t2[N2-1], t2[N2-1]-t2[N2-2]) if N2 > 1 \
+                           else t_end-t2[N2-1]
                     # s2 needs adjustment due to change of isi2
                     # s2 = dt_p2*(t_end-t2[N2-1])/isi2
                     # Eero's correction: no adjustment
@@ -330,7 +336,8 @@ def spike_profile_cython(double[:] t1, double[:] t2,
                 else:
                     t_f1 = t_aux1[1]
                     dt_f1 = dt_p1
-                    isi1 = fmax(t_end-t1[N1-1], t1[N1-1]-t1[N1-2])
+                    isi1 = fmax(t_end-t1[N1-1], t1[N1-1]-t1[N1-2]) if N1 > 1 \
+                           else t_end-t1[N1-1]
                 if index2 < N2-1:
                     t_f2 = t2[index2+1]
                     dt_f2 = get_min_dist_cython(t_f2, t1, N1, index1,
@@ -339,18 +346,14 @@ def spike_profile_cython(double[:] t1, double[:] t2,
                 else:
                     t_f2 = t_aux2[1]
                     dt_f2 = dt_p2
-                    isi2 = fmax(t_end-t2[N2-1], t2[N2-1]-t2[N2-2])
+                    isi2 = fmax(t_end-t2[N2-1], t2[N2-1]-t2[N2-2]) if N2 > 1 \
+                           else t_end-t2[N2-1]
             index += 1
         # the last event is the interval end
         if spike_events[index-1] == t_end:
             index -= 1
         else:
             spike_events[index] = t_end
-            # the ending value of the last interval
-            isi1 = max(t_end-t1[N1-1], t1[N1-1]-t1[N1-2])
-            isi2 = max(t_end-t2[N2-1], t2[N2-1]-t2[N2-2])
-            # s1 = dt_f1*(t_end-t1[N1-1])/isi1
-            # s2 = dt_f2*(t_end-t2[N2-1])/isi2
             s1 = dt_f1
             s2 = dt_f2
             y_ends[index-1] = (s1*isi2 + s2*isi1) / isi_avrg_cython(isi1, isi2)