Switched from std::sort to insert-sort in cbm::algo::tof::Calibrate (faster for pre-sorted data).

algo/detectors/tof/Calibrate.cxx

@@ -52,8 +52,7 @@ namespace cbm::algo::tof
 
     std::fill(mChannelDeadTime.begin(), mChannelDeadTime.end(), std::numeric_limits<double>::quiet_NaN());
 
-    for (const auto& entry : digiIn) {
-      CbmTofDigi digi     = entry;
+    for (const auto& digi : digiIn) {
       const double SmType = digi.GetType();
       const double Sm     = digi.GetSm();
       const double Rpc    = digi.GetRpc();
@@ -81,14 +80,14 @@ namespace cbm::algo::tof
       }
       mChannelDeadTime[chanIdx] = digi.GetTime() + rpcPar.channelDeadtime;
 
+      // Create calibrated digi
+      CbmTofDigi& pCalDigi = calDigiOut.emplace_back(digi);
+
       // Check if channel sides need to be swapped
       if (rpcPar.swapChannelSides && 5 != SmType && 8 != SmType) {
-        digi.SetAddress(Sm, Rpc, Chan, (0 == Side) ? 1 : 0, SmType);
+        pCalDigi.SetAddress(Sm, Rpc, Chan, (0 == Side) ? 1 : 0, SmType);
       }
 
-      // Create calibrated digi
-      CbmTofDigi& pCalDigi = calDigiOut.emplace_back(digi);
-
       // calibrate Digi Time
       pCalDigi.SetTime(pCalDigi.GetTime() - chanPar.vCPTOff[Side]);
 
@@ -120,8 +119,20 @@ namespace cbm::algo::tof
     }
 
     /// Sort the buffers of hits due to the time offsets applied
-    std::sort(calDigiOut.begin(), calDigiOut.end(),
-              [](const CbmTofDigi& a, const CbmTofDigi& b) -> bool { return a.GetTime() < b.GetTime(); });
+    // (insert-sort faster than std::sort due to pre-sorting)
+    for (std::size_t i = 1; i < calDigiOut.size(); ++i) {
+      CbmTofDigi digi = calDigiOut[i];
+      std::size_t j   = i;
+      while (j > 0 && calDigiOut[j - 1].GetTime() > digi.GetTime()) {
+        calDigiOut[j] = calDigiOut[j - 1];
+        --j;
+      }
+      calDigiOut[j] = digi;
+    }
+
+    //  Kept for possible unsorted input
+    //  std::sort(calDigiOut.begin(), calDigiOut.end(),
+    //  [](const CbmTofDigi& a, const CbmTofDigi& b) -> bool { return a.GetTime() < b.GetTime(); });
 
     monitor.fTime = xpu::pop_timer();
     //L_(info) << MakeReport("CalibrateTime", monitor.fTime);