cutflow table generic class

rooutil/inc/cutflow.hh

@@ -0,0 +1,83 @@
+/* this file will formulate a cut flow table in the terminal for a given set of cuts
+
+usage:
+    std::vector<CutflowEntry> data = {
+    {"Initial Events", util.GetNEvents()},
+    {"is electron", n_electrons},
+    {"is downstream", n_downstream},
+    {"trkqual.result > 0.2", n_trkqual},
+    {"t0err > 0.9 ns", n_t0err},
+    {"|d0| < 100 mm ", n_d0},
+    {"450 < rmax < 680 mm ", n_rmax},
+    {"has CRV coincidence", n_crv}
+    };
+
+    printCutflowTable(data);
+
+*/
+
+#ifndef cutflow_hh_
+#define cutflow_hh_
+#include <format>
+// Structure to hold cutflow data
+struct CutflowEntry {
+    std::string cut_name;
+    long long passed_count;
+};
+
+void printCutflowTable(const std::vector<CutflowEntry>& entries) {
+    if (entries.empty()) {
+        std::cout << "No cutflow data to display." << std::endl;
+        return;
+    }
+
+    // Define column widths
+    const int cut_name_width = 30;
+    const int passed_width = 15;
+    const int prev_change_width = 15;
+    const int initial_change_width = 15;
+
+    // Print the table header
+    std::cout << std::format("{:<{}} {:>{}} {:>{}} {:>{}}\n",
+                             "Cut", cut_name_width,
+                             "Passed", passed_width,
+                             "% Change (Prev)", prev_change_width,
+                             "% Change (Initial)", initial_change_width);
+
+    // Print a separator line. std::format does not have the fill-character side effect.
+    std::cout << std::format("{:-<{}}\n", "", cut_name_width + passed_width + prev_change_width + initial_change_width + 3);
+
+    const long long initial_count = entries[0].passed_count;
+    long long last_count = 0;
+
+    for (size_t i = 0; i < entries.size(); ++i) {
+        const auto& entry = entries[i];
+
+        std::string percent_prev_str;
+        if (i > 0 && last_count > 0) {
+            double percent_change_prev = static_cast<double>(entry.passed_count - last_count) / last_count * 100.0;
+            percent_prev_str = std::format("{:+.2f}%", percent_change_prev);
+        } else {
+            percent_prev_str = "N/A";
+        }
+
+        std::string percent_initial_str;
+        if (initial_count > 0) {
+            double percent_change_initial = static_cast<double>(entry.passed_count - initial_count) / initial_count * 100.0;
+            percent_initial_str = std::format("{:+.2f}%", percent_change_initial);
+        } else {
+            percent_initial_str = "N/A";
+        }
+
+        std::cout << std::format("{:<{}} {:>{}} {:>{}} {:>{}}\n", 
+                                 entry.cut_name, cut_name_width,
+                                 entry.passed_count, passed_width,
+                                 percent_prev_str, prev_change_width,
+                                 percent_initial_str, initial_change_width);
+
+        last_count = entry.passed_count;
+    }
+}
+
+#endif
+