Merge pull request #24 from mroguljic/PRbranch

module to read TEfficiencies and make corrections

TIMBER/Framework/src/EffLoader.cc

+#include <string>
+#include "TFile.h"
+#include "TEfficiency.h"
+
+/**
+ * @class EffLoader
+ * @brief Generic histogram loader with methods to return bin values.
+ */
+class EffLoader {
+    private:
+        TFile *file;
+        TEfficiency *efficiency; //!< Histogram object
+        int binx;
+        int globalbin;
+        float effval;
+        float effup;
+        float effdown;
+
+    public:
+        /**
+         * @brief Empty constructor
+         */
+        EffLoader(){};
+        /**
+         * @brief Construct a new EffLoader object
+         * 
+         * @param filename File to access.
+         * @param histname Histogram name in the file.
+         */
+        EffLoader(std::string filename, std::string histname);
+        /**
+         * @brief Evaluate by global bin number.
+         * 
+         * @param globalbin 
+         * @return std::vector<float> {nominal value, up error+nominal, down error+nominal}
+         */
+        std::vector<float> eval_byglobal(int globalbin);
+        /**
+         * @brief Evaluate by per-axis bin numbers.
+         * 
+         * @param binx 
+         * @param biny
+         * @param binz 
+         * @return std::vector<float> {nominal value, up error+nominal, down error+nominal}
+         */
+        std::vector<float> eval_bybin(int binx, int biny = 0, int binz = 0);
+        /**
+         * @brief Evaluate by axis value.
+         * 
+         * @param xval 
+         * @param yval
+         * @param zval
+         * @return std::vector<float> {nominal value, up error+nominal, down error+nominal}
+         */
+        std::vector<float> eval(float xval, float yval = 0, float zval = 0);
+            
+};
+
+EffLoader::EffLoader(std::string filename, std::string effname) {
+    file = TFile::Open(filename.c_str());
+    efficiency = (TEfficiency*)file->Get(effname.c_str());
+}
+
+std::vector<float> EffLoader::eval_byglobal(int globalbin){
+    effval  = efficiency->GetEfficiency(globalbin);
+    effup   = effval + efficiency->GetEfficiencyErrorUp(globalbin);
+    effdown = effval - efficiency->GetEfficiencyErrorLow(globalbin);
+    return {effval,effup,effdown};
+}
+
+std::vector<float> EffLoader::eval_bybin(int binx, int biny, int binz){
+    globalbin    = efficiency->GetGlobalBin(binx, biny, binz);
+    return eval_byglobal(globalbin);
+}
+
+std::vector<float> EffLoader::eval(float xval, float yval, float zval){
+    globalbin    = efficiency->FindFixBin(xval, yval, zval);
+    return eval_byglobal(globalbin);
+}
\ No newline at end of file