Checkpointing first working version

Author: peterfpeterson

CMakeLists.txt

@@ -58,3 +58,7 @@ add_executable(pushback pushback.cpp)
 #
 add_executable(nexusopenclose nexusopenclose.cpp)
 target_link_libraries(nexusopenclose PRIVATE Nexus::nexus Nexus::nexuscpp)
+
+#
+add_executable(eventlistb2 eventlistb2.cpp)
+target_link_libraries(eventlistb2 PRIVATE Nexus::nexus Nexus::nexuscpp)

eventlistb2.cpp

@@ -0,0 +1,79 @@
+#include <iomanip>
+#include <iostream>
+#include <memory>
+#include <nexus/NeXusFile.hpp>
+#include <sstream>
+#include <stdio.h>
+#include <string>
+#include <sys/time.h>
+#include <vector>
+
+using std::cout;
+using std::endl;
+using std::string;
+using std::vector;
+
+// copied from nexus to break out of iteration
+static string const NULL_STR("NULL");
+// things we care about
+static string const NXEVENT_DATA("NXevent_data");
+static string const GROUP_ERROR("bank_error_events");
+static string const GROUP_UNMAPPED("bank_unmapped_events");
+// event fields
+static string const FIELD_TOF("event_time_offset");
+static string const FIELD_DETID("event_id");
+static string const FIELD_PULSE_TIME("event_time_zero");
+static string const FIELD_PULSE_INDEX("event_index");
+
+// thing that
+template <typename T> std::unique_ptr<std::vector<T>> readData(NeXus::File &file, std::string const &fieldname) {
+  file.openData(fieldname);
+  auto const info = file.getInfo();
+
+  auto data = std::make_unique<std::vector<T>>(info.dims[0]);
+  file.getData(*data);
+  file.closeData();
+
+  return data;
+}
+
+// -------------------------------------------------------------------
+int main(int argc, char *argv[]) {
+  if (argc != 2) {
+    cout << "usage: " << argv[0] << " <filename>" << endl;
+    return 1;
+  }
+
+  string filename(argv[1]);
+  cout << "Trying with: " << filename << endl;
+  for (std::size_t i = 0; i < 1; i++) {
+    NeXus::File file(filename);
+    file.openGroup("entry", "NXentry");
+
+    // loop over entries
+    std::pair<string, string> temp;
+    while (true) {
+      temp = file.getNextEntry();
+      // both being null string means there are no more entries
+      if (temp.first == NULL_STR && temp.second == NULL_STR)
+        break;
+
+      // only process event data groups
+      if (temp.second == NXEVENT_DATA) {
+        if (temp.first == GROUP_ERROR || temp.first == GROUP_UNMAPPED)
+          continue;
+        std::cout << "reading " << temp.first << std::endl;
+        file.openGroup(temp.first, NXEVENT_DATA);
+
+        // these types and names are brittle
+        auto pulseIndex = readData<uint64_t>(file, FIELD_PULSE_INDEX);
+        auto pulseTimes = readData<double>(file, FIELD_PULSE_TIME);
+        auto tof = readData<float>(file, FIELD_TOF);
+        auto detid = readData<uint32_t>(file, FIELD_DETID);
+
+        file.closeGroup();
+      }
+    }
+    file.close();
+  }
+}