Move the per-segment semi-coherent calculation to sep. functions

This helps with timing to see which functions are being called
repeatedly

pyfstat/core.py

@@ -917,9 +917,18 @@ class SemiCoherentSearch(BaseSearchClass, ComputeFstat):
         detStat = 0
         if record_segments:
             self.detStat_per_segment = []
-        for tstart, tend in zip(self.tboundaries[:-1], self.tboundaries[1:]):
+
+        self.windowRange.tau = int(self.Tcoh)  # TYPE UINT4
+        for tstart in self.tboundaries[:-1]:
+            d_detStat = self._get_per_segment_det_stat(tstart)
+            detStat += d_detStat
+            if record_segments:
+                self.detStat_per_segment.append(d_detStat)
+
+        return detStat
+
+    def _get_per_segment_det_stat(self, tstart):
         self.windowRange.t0 = int(tstart)  # TYPE UINT4
-            self.windowRange.tau = int(tend - tstart)  # TYPE UINT4
 
         FS = lalpulsar.ComputeTransientFstatMap(
             self.FstatResults.multiFatoms[0], self.windowRange, False)
@@ -944,11 +953,8 @@ class SemiCoherentSearch(BaseSearchClass, ComputeFstat):
         if np.isnan(d_detStat):
             logging.debug('NaNs in semi-coherent twoF treated as zero')
             d_detStat = 0
-            detStat += d_detStat
-            if record_segments:
-                self.detStat_per_segment.append(d_detStat)
 
-        return detStat
+        return d_detStat
 
 
 class SemiCoherentGlitchSearch(BaseSearchClass, ComputeFstat):