Added empty spike check in swarmsplitter.check_CCG

Author: Jacob Pennington

kilosort/swarmsplitter.py

@@ -53,7 +53,9 @@ def bimod_score(xproj):
 def check_CCG(st1, st2=None, nbins = 500, tbin  = 1/1000):
     if st2 is None:
         st2 = st1.copy()
-    K , T= compute_CCG(st1, st2, nbins = nbins, tbin = tbin)
+    K , T = compute_CCG(st1, st2, nbins = nbins, tbin = tbin)
+    if len(st1) == 0 or len(st2 == 0) or T == 0:
+        return False, False
     R12, Q12, Q00 = CCG_metrics(st1, st2, K, T,  nbins = nbins, tbin = tbin)
     is_refractory    = R12<.1  and (Q12<.2  or Q00<.25)
     cross_refractory = R12<.25 and (Q12<.05 or Q00<.25)